Pinterest Inc (PINS) 2021 Q1 法說會逐字稿

Good day, and thank you for standing by. Welcome to the Pinterest First Quarter Earnings Conference Call. (Operator Instructions) Please be advised that today's conference is being recorded. (Operator Instructions)

And without a further ado, I would like to welcome your host for today, Ms. Jane Penner, Head of Investor Relations. Ma'am, the floor is yours.

Thank you, Karl. Good afternoon, and thank you for joining us. Welcome to Pinterest's Earnings Call for the First Quarter ended March 31, 2021. I'm Jane Penner, Head of Investor Relations for Pinterest.

Joining me today on the call are Ben Silbermann, Pinterest's President and CEO; and Todd Morgenfeld, our Chief Financial Officer and Head of Business operations.

Now I'll cover the safe harbor. Some of the statements that we make today regarding our performance, operations and outlook, including the impact of the COVID-19 pandemic may be considered forward-looking, and such statements involve a number of risks and uncertainties that could cause actual results to differ materially. In addition, our results, trends and outlook for Q2 2021 preliminary are not an indication of future performance. We are making these forward-looking statements based on information available to us as of today, and we disclaim any duty to update them later unless required by law. For more information, please refer to the risk factors discussed in our most recent Forms 10-Q or 10-K filed with the SEC and available on the Investor Relations section of our website.

During this call, we will present both GAAP and non-GAAP financial measures. A reconciliation of non-GAAP to GAAP measures is included in today's earnings press release and the letter to shareholders, which are distributed and available to the public through our Investor Relations website located at investor.pinterestinc.com.

And now I'll turn the call over to Ben.

Hello, everyone. Thanks, Jane, and thanks, everyone, for joining today. I just want to start by acknowledging that last March was the start of the pandemic, and we're not still fully through it. Leading through this difficult time has been a humbling experience, and I'm deeply proud of everyone's interest for their commitment to our teams, to our partners and to our Pinners.

I'm also proud that during the challenging time, we've shared inspiration with hundreds of millions of people around the world and help businesses reach customers when their physical storefronts may have been closed. Like all of you, I look forward to seeing the pandemic end and look forward to a time where we can be together once again.

Now today, Todd is going to go into specifics regarding our financial results, and I'll talk about how we're thinking about Pinterest as we begin to come out of the pandemic. But I want to start by saying that this was a strong quarter. We're confident in our strategy and excited about the investments we're making. Let me offer some more details.

First, more people are using Pinterest to inspire and plan their lives than ever before. Our monthly active users grew 30% to more than 478 million users globally with strong growth coming from Gen Z, a persistent trend that we've seen for several quarters. We also saw product searches grow more than 20x year-over-year. Increasingly, people see Pinterest as a place to not only get inspired but also to shop.

Second, our business is strong. Advertisers are inspiring Pinners, and they're generating sales on Pinterest. We grew revenue 78% year-over-year driven by more small- to mid-sized advertisers and further international expansion. Businesses appreciate that Pinterest is a positive place, where people are coming to get new ideas for their life. Well-targeted ads make Pinterest more useful rather than being a distraction to what people are there to do. And these businesses are seeing strong business results driven significantly by the investments we've made to make our advertising products more effective and easier to use.

Third, we are working to help people feel more inspired in every aspect of their life, and that starts with giving people the most inspiring content. We continue to invest in new inspiring forms of content like Story Pins. Story Pins on Pinterest are different from stories on other platforms. They're less about what somebody else did and more about what you could do now and in the future. Unlike stories in other platforms, they never disappear, and they don't just show up for followers. They show for anybody looking for an idea like yours, like what you need to do to get your home decorated, that dinner made or that workout done.

In Q1, we started distributing Story Pins more broadly throughout our creator ecosystem, and we're excited about the uptake we're already seeing. As we continue to distribute Story Pins, Pinners will need to learn new ways to navigate and use Pinterest. This could change engagement in the coming quarters, but we're confident that over time, investing in new media formats like Story Pins will inspire our community, provide new ways to engage with Pinterest more deeply and create new revenue opportunities for creators and businesses alike.

We're also making it easier for Pinners to take out what these they see and make them real. The number of Pinners engaging with shopping surfaces on Pinterest has grown over 200% in the last year as Pinners look to go from inspiration to purchase. At the end of Q1, revenue from retailers with sales objectives were 20% of total revenue, and all of this shows that we're making the real traction with shopping on Pinterest. As a next step, we're excited to begin testing seamless on platform transactions later this year.

And finally, we continue to expand our business globally. We launched advertising in Brazil this quarter, an important milestone in growing our global ads business. We expanded our Shopify integration to 27 additional countries to help us further build Pinterest as the destination for shopping. And for the first time, our international business is nearly 20% of total revenue.

We're seeing a lot of strength in our business, but it's important to note that since the pandemic began, we've seen a correlation between stay-at-home orders and engagement on Pinterest. Pinterest has always been popular for home improvement, rescue collection and lesson planning. And naturally, many of us did more of these things during our time at home, which brought more people to Pinterest in 2020.

As pandemic lockdowns were eased in some parts of the world during mid-March, we began to see signs of less engagement and user growth on Pinterest, and we assume this means people are spending more time off-line. While it's impossible to say how people act as we enter the summer months, we anticipate this trend will continue.

Finally, I'd like to note that like the entire online advertising industry, we're faced with changes to the privacy landscape. We've talked for over a year about the steps we're taking to ensure advertisers understand the effectiveness of their ads while also keeping Pinner privacy in mind. This includes investments in new first-party solutions, enhancements to ad targeting. People naturally come to Pinterest to search, shop and find ideas for brands and creators. Personalization based on its onset activity won't be affected by the upcoming changes. That said, it's still early days. It is not yet clear what the long-term impact will be.

To close, I'd like to note that this past year has reinforced the importance of our mission. Pinterest is not the place to read the news or debate politics with your cousin or compare yourself to other people. It is a positive place to be inspired and get ideas in your future life. This is reflected in our content and ad policies, our efforts to combat COVID vaccine misinformation, our new creator code and comment moderation tools designed to keep new content formats positive and inspiring and our continued focus on engineering products for positivity with new inclusive search features like skin tone ranges now available in 13 countries. I'm excited about how far we've come over a challenging year and even more excited about where we go in the future.

I'll now pass it on to Todd.

Thanks, Ben. I'll share some further details on the trends we saw in the first quarter and provide a preliminary outlook for Q2. Let's start with a quick summary of the headlines, and then we'll go into more detail.

As Ben mentioned, we had a really strong first quarter. Year-over-year revenue growth accelerated to 78%, with adjusted EBITDA margins of 17%. Monthly active user growth remains strong, with all regions once again showing good momentum.

First quarter revenue growth was propelled by 2 main drivers. First, we saw strong momentum from mid-market and managed small advertisers, who are increasingly finding value in our conversion-focused ad products and the automation of our ad stack. Second, our international business performed really well, growing 170% year-over-year in the first quarter. We're seeing the highest growth in Western Europe and Canada, where we're continuing to expand our sales coverage. Both of these trends show in the growth and diversification of our advertiser base.

The drivers of our growth in the first quarter, including performance ads products for small- and medium-sized businesses, automation and advertiser diversification, probably sound familiar because we've been talking about our investment in them since our IPO a couple of years ago. As we begin to dig into newer strategic initiatives, such as building a native content ecosystem, I think it's worth taking a minute to draw your attention to our playbook for these kinds of investments.

In general, our philosophy is to deliver value to Pinners first, then lean into scale and monetize. This worked well for the international rollout of our ads business as well as for our shopping initiative. For international, we executed a blueprint for ad sales in the U.S. before scaling it globally. We knew that global users were there to support an expansion, but we got the gears working properly in the U.S. before leaning in. This worked well. We're serving ads in 29 countries today, and international revenue comprised almost 20% of total revenue in the first quarter. And we just launched in our first Latin American country, Brazil, with Mexico coming in May.

For shopping, we prioritize building an organic shopping experience for Pinners with high quality inventory, catalog uploads and discovery services before really leaning into monetization. This strategy has also been very effective to date, though it's still relatively early days. Not only have we dramatically scaled shopping engagement on the platform, we shared for the first time today that ad revenue from retailers optimizing for sales on Pinterest is now a meaningful part of our financial performance.

In both our international ads rollout and in shopping, we serve the Pinner first by getting the fundamental infrastructure in place and only then scaling and monetizing the experience. We're running the same playbook as we build a native content ecosystem. We're currently focused on delivering value to Pinners by making it easier for creators to make great content and learning the optimal mechanisms to distribute that content. It's very early in our journey to achieve scale or drive meaningful monetization at this point. We're currently investing R&D and sales and marketing resources to get our content ecosystem off the ground. And when we're confident that we understand how best to deliver value to Pinners, we'll lean in harder to scale and monetize. That may take the form of additional investment, but it's too early to know exactly what that looks like today.

Turning to our preliminary outlook for Q2. Ben mentioned that we have both headwinds and potential tailwinds for engagement and MAU growth that may play out over the next couple of quarters. In Q2, we expect global monthly active users to grow in the mid-teens and U.S. monthly active users to be about flat on a year-over-year percentage basis. We expect to grow revenue about 105% year-over-year in Q2.

As we think about the first quarter and the full year, we believe the momentum and returns we're seeing from our investments in ad tools and sales coverage expansion should continue. Starting at the end of March, we began to lap easier year ago revenue comparisons, which will continue through Q2 and is factored into our guidance.

Before opening up for questions, I also want to touch on expenses. We continue to invest in the growth of the business in accordance with our big strategic priorities of inspiring content, Pinner experience, advertiser success and shopping. In the first quarter, we grew our headcount 17% year-over-year. We expect our sequential non-GAAP OpEx growth to be in the mid-teens on a percentage basis as we continue to ramp investments in our long-term initiatives and growth drivers. And as a reminder, we're investing in marketing campaigns to bolster comprehension and brand awareness throughout the year. Those campaign launches in Q2 will drive a substantial or sizable increase in our variable spend.

Thank you to the teams at Pinterest, our advertising partners and all of the people that come to Pinterest to find inspiration. And with that, we can open it up for questions.

Operator, we are ready for our first question.

(Operator Instructions) Our first question comes from the line of Ross Sandler from Barclays.

Todd, just a question about the guidance. So obviously, we've got pretty robust revenue growth here in the second quarter. But you said the U.S. is going to be flat, and that would be a down sequential for MAU. So how much wiggle room do you think there is still to increase ad load given the massive revenue growth and the flat user growth? And can you give us any context around, if you look at last quarter or the last couple of quarters, the trade-off between impression growth and eCPM in the U.S.?

Yes. Thanks for the question, Ross. So I understand the question really about user growth and the connection to revenue. So I'll go through a couple of things. And hopefully, this gets to the essence of the question. I would say sequentially, we're unwinding some of the pulled forward user growth that we had last year and some of the engagement from the unprecedented COVID period that we all went through over the last year. Kind of an exacerbated version of the typical seasonality that we would see going into the summer, but compounded by unwinding some of the restrictions that we had around COVID.

We're also, it's worth noting, making, as I mentioned, investments in comprehensive marketing, and a lot of what Ben talked about around our creators and native content efforts are designed to drive long-term engagement. So I don't want to leave that unattended to. But it's really worth noting, and this is something that I'm glad you asked about, it's worth noting that our investments to more efficiently utilize our unique engagement, that commercial mindset and planning behavior that Pinners bring to Pinterest, it's working.

We've made investments in products and in sales coverage. As we talked last time, our vision over the long term is to have advertisers bring their budget, their goals and their content, and we automate the rest. And while we have a long way to go before we get there, we've made it a lot easier for advertisers to onboard, scale and see results, especially in the SMB space. And we did that through especially ROI accountable conversion-led performance ads that generate higher potential effective CPMs over time. We saw that unfold over the course of last year through automated bidding across traffic, conversion optimization and shopping objectives. We're working on a similar automation exercise now called campaign budget optimization, which allows for better delivery across ad groups instead of just within ad groups, so continuing that automation theme. And we'll launch automated bidding for awareness objectives over the course of this year, too. So that long-term trend around automation continues.

We've accelerated further through partnerships like the one with Shopify, it will be expanded internationally. We've partnered all that investment in product through an improved coverage model. We focused on growing our managed SMB coverage, which is now nearly half of our revenue. And you saw the results we posted internationally with opening new markets in places like Brazil and Mexico next. At nearly 20% of our revenue, that's up significantly as a percentage of our mix.

But what I wanted to make sure we highlight, and I think this is your question, is that we are more efficiently using or utilizing the unique engagement that we have on Pinterest, and that strategy is working. So when you boil it down to your question about ad impressions and realized pricing or effective CPMS, our revenue growth was mostly driven by effective CPM gains in the quarter versus impressions, especially in our performance products. And the thing that most stood out to me was that our ad load in the U.S. and globally actually ticked down in the first quarter year-over-year despite U.S. revenue growing 65% and overall revenue growing 78%. So we are much more efficiently using -- utilizing the ad supply that we have because we've automated -- we've built the right products with the right automation, and ads are working for advertisers on the platform. Does that get to your question?

Yes, that's super helpful. Appreciate the color.

Our next question comes from the line of Brian Nowak from Morgan Stanley.

I have 2. I want to ask the first one on sort of users and engagement as the world reopens and sort of post shelter in. I think there are some use cases on the platform around home design that could benefit from the housing market or party planning that benefit from reopening, or maybe even travel, or there could be a case that maybe you could retain some of this engagement. I guess talk to us about why you are or are not seeing that as a way to sort of retain some of these users in that engagement as the world reopens. And what do you have to invest in to sort of capitalize on that?

And then the second one, just on IDFA and some of the platform changes. Talk to us about how you think about further emphasizing on platform transactions for shopping to sort of make the advertisers better mitigate -- better manage through the IDFA uncertainty?

Sure, Brian. I can start off. Your first question is really about users and engagement, and what I heard was it seems like there are a lot of core categories that could be quite resilient, how are we thinking about that post COVID. So taking a step back, Todd mentioned a couple of times that the way we see it is that during COVID, people spend a lot more time online. They spend a lot more time creating new patterns and behaviors for their stay at home life, and Pinterest was the beneficiary of that. And thankfully, when more people spend time outside their home out there in the world, we expect some of that engagement to go away. That said, I'd observe a few things, one of which that you brought up.

First, in a lot of the core categories, particularly the commercially strong categories, things like interior design, fashion, we're still seeing a really good resilience, and we have early data that indicates that engagement in those core commercial categories is going to be stickier than engagement overall. And we think that's a good thing. That's evidenced in the strength in uptick in shopping surfaces, the significant increase in the number of shopping-related searches as well as what we see in overall user behavior.

Second, as you mentioned, there could be certain tailwinds but we try to communicate what we've seen rather than what we think in the future. To your point, historically, certain events, whether it's Halloween, holidays, wedding planning, they were big drivers in engagement on Pinterest. We saw that go away, but the net time online kind of went over that during the pandemic. So there could be tailwinds. We're just not baking them in. And so all of that paints a picture where we do expect, as Todd mentioned, flattish growth in the U.S. But over the long term, we think there's a lot to be optimistic about. In addition to the content efforts that we're undertaking now, we mentioned that we're going to be doing our first brand campaign and generally just improving the quality of the Pinner experience over the long term. So that's how we're kind of thinking about those pieces coming together. Before going on, does that kind of answer your question?

Yes. That's perfect.

Great. The second question I heard was really about IDFA and what are the thoughts that we have on particularly shopping to help retailers get a little bit closer to Pinterest when they're near that point of transaction. So as an overview, and this is obviously a new territory, but we've been talking about it kind of with the community for more than a year, we put in place efforts to improve first-party measurement solutions through things like our shopping solutions. But more to the point, we've also really increased the amount of engagement that Pinners have on shopping surfaces more directly.

This year, for example, we allow Pinterest users to pivot any search into a shopping search, and that significantly increased engagement on shopping surfaces. This has been part of our strategy all along. If you rewind a couple of quarters, our strategy was, one, we're going to increase the amount of high-quality inventory with things like our catalog uploader, which we expanded with multi-feed as well as our partnerships with folks like Shopify. It was, two, to make it easier for Pinners to get to those products, and that's exemplified an increase in the number of shopping surfaces as well as being able to pivot from search to shopping search. The next step in that journey will be early pilots in testing seamless checkout and removing the friction, and that's been the sequence that we're pursuing for a while, and early results are really good.

Our next question comes from the line of Mark Mahaney.

You talked about the upcoming potential for, I think, seamless on-platform transactions. So I guess the question, Todd, would be, does that -- maybe way too early, but would that open the opportunity for new types of revenue models?

And then secondly, just an ongoing broad question about closing the ARPU gap between your international markets and the U.S. market, and of course, it's going to be broad and wide for a while. But are there any new learnings you've had about how to get that to more in line with maybe what you see at some of the other advertising platforms that are out there? Is it just more sales coverage, more self-serve tools? Are there new methods you found that can help power that or close that gap somewhat more?

Thanks, Mark. So I heard 2 questions in there. The first was around new revenue models that could be associated with native checkout and the second was around how that ARPU trend may look over time and drivers. So on the new revenue model point, I think it's probably worth pausing and going back to some of the opening comments I had about what we endeavor to do when we make new investments.

I was really excited last year when we said we know our users come to find inspiration and then create real action out of those inspirational items that they get off of Pinterest, and so we focused on getting the right inventory of shoppable products on the platform and to make those products discoverable for our users. That was the first way of addressing that desire to buy that our users express around, desire to buy what they found on Pinterest.

Through all the work on catalog uploads and work on the organic product to serve more natural shopping journeys that users go through, we were able to fulfill that request. And so as Ben mentioned, the next step might be, later in the year, testing native checkout. I would say we're trying to make sure that the user experience works first, and we're not committing at this point to any new revenue models. But over the longer term, that's something we could evaluate.

Second, on the ARPU opportunity, I think what I was mentioning before around all of the investments we've made in product and in coverage bringing -- with the long-term goal of having advertisers bring in their budget, their goals and their content and automating the rest, serving especially the SMB market and diversifying our advertiser base, allowing them to easily onboard scale and see results from their spend, we've had a great track record over the last year of delivering that kind of automation, and we've invested in exactly the right sales coverage model in the U.S. and internationally to generate demand against that. That has been the recipe for driving ARPU growth. I think we posted 50% ARPU growth in the U.S. last quarter. It's a result of all of those investments in product and coverage.

We've seen that, that model works in international markets, too. We're seeing great traction. And as I mentioned, we're now at 20 -- nearly 20% of our overall revenue from international markets through a similar playbook. It's a playbook that we built as a first step in some of the English-speaking countries outside of the U.S. and then refined in Western Europe, most notably in France and Germany, and are now rolling out, it's very, very early days, but are now rolling out in Latin America. We've talked historically about how Pinners come to our platform with a similar mindset in international markets, and so a lot of the international opportunity is really down to execution. And I think we've got the right team in place to deliver against that over time. I'm super encouraged by the progress we've made and the opportunity ahead.

Our next question comes from the line of Lloyd Walmsley from Deutsche Bank.

Okay. Two pretty related questions. I guess, first, on the shopping stuff, it does sound like you're seeing a lot of growth in attributed conversions. So beyond getting better visibility in conversions, curious, do you think your users are starting to engage in Pinterest more throughout the funnel, closer to the point of purchase such that you can get more credit for this engagement than you have in the past beyond simply more visibility into conversions?

And then the second one, as you look beyond maybe simple ad impressions to growth in kind of commercial actions, you talked about doubling measured conversions, but do you see long-term runway to kind of keep growing high-intent actions on the platform beyond simply impressions, whether that's clicks or checkouts? Like is there still a ton of runway there to drive monetization without really depending on pure price? Kind of anything you can share there would be great.

Lloyd, I can start with the first part and maybe Todd can kind of add more to the second one. The question, as I understood it was, do we feel that users on the platform are really going through more of the funnel who have seen Pinterest increasingly as the destination to shop, and the answer to that in short is yes. So if we rewind a little bit and think about kind of where our strategy was, a couple of years ago, we knew there was a lot of commercial intent on the platform, but a major pain point for Pinners was they weren't able to get to the product and then to make it purchase upon an easy way. And so the first thing that we really worked on was increasing the amount of shoppable inventory. And as mentioned before, things like the increase in the number of catalog uploads, it's up 14x in the last 12 trailing months, has really improved the quality of the inventory.

The next step then was to begin showing users that when they were on a piece of content, they could find high-quality products with up-to-date metadata, and that's been sort of the second leg of the stool. So increasingly, if you use Pinterest, when you see a product, you'll find that there's up-to-date pricing information, stock information, and that's a continuous improvement in quality.

Over the last 1.5 quarters, I would say, where we've seen real traction is then beginning to let users pivot from what we might call inspiration mode into shopping mode by engaging in shopping-only surfaces. Some of those surfaces are pivots off things like search, others are looking underneath a large image pin and then being able to go into a feed of related products connected either by a similar look, a similar brand or a similar price point. We think that engagement with those surfaces is indicative of higher shopping intent, and we noticed really strong purchasing behavior off of those surfaces.

So now that those foundational pieces are laid, the next thing we want to test is removing friction from the transaction. And that's something, again, that will pilot, as Todd mentioned, try to get the experience really good and then begin to roll it out more broadly. So I think the short answer is yes. The longer answer is that's the journey we're on. It's not going to be a flip to switch, but we're hearing from Pinners, we're seeing an engagement in shopping surfaces, we're seeing in the growth in attributable conversions that Pinners are increasingly seeing it as a place where they cannot only get inspired, but they can also buy.

And Lloyd, the only thing I would really add to that, I think that's a good summary of the user experience that we've been building toward. But as an advertiser, you can imagine that maps, that user journey maps really well to advertising objectives ranging from awareness to consideration to purchase. And one of the things that we hear when we talk to CMOs is value of Pinterest as a full funnel advertising experience across all of those objectives.

But as attributed conversions and purchase activities increased, that was the reason we called out the stat about 20% of our revenue coming from retailers with conversion objectives because it's an important trend. Lot of our early business was built around awareness and consideration objectives or traffic-based buying. But what we've seen recently is that shopping ads or catalog-based ads, coupled with conversion optimization ads with checkout or add to cart objectives, are now -- for the retail community are now 20% of our overall revenue. And that seems like a mouthful, but it's designed to show exactly what Ben described. The user experience is more lower funnel, and we're increasingly taking our users from inspiration to action through that purchase journey, and it's showing up in our advertising results.

Our next question comes from the line of Justin Post from BofA.

Great. Maybe one for Ben and one for Todd. Ben, in the U.S. market and more mature European markets, how do you think about driving user growth over the next 2 years? Is it things like shopping that could attract a little bit different audience or categories like travel or autos that you think could really take off? Any signs there that encourage you?

And then, Todd, could you revisit the expense guidance? I'm assuming it excludes the charitable contribution. Does that include cost of goods sold? Could you just revisit the quarter-over-quarter expense guidance?

Thanks for the question, Justin. What I heard was, in more mature markets, where do we see growth coming from? So we said over the last few quarters that there's a sustained trend, particularly Gen Z users, engaging with Pinterest more and more. I think that's pretty interesting because, historically, Pinterest has attracted a lot of millennials and folks that were a little bit older. And there is this question mark on whether Gen Z users, who have a strong interest in socializing with their friends, are also interested in investing time to get creative ideas for themselves and to explore their hobbies and interests. And I think that what we've seen is the answer to that is a resounding yes. While there are some category overlaps, there are also category differences. We see this is a group of users that loves fashion. They love exploring their creativity. They're looking now more and more into things like food. This is a group that's not yet really looking into decorating. And so it kind of reflects the same spirit of what Pinterest is about but at a different stage of life, and we see a lot of growth opportunity there.

Past that, we do see 2 big opportunities to just improve the quality of the experience, both the utility and how inspirational it is. I spoke a little bit about Story Pins as a new media format. And we're talking about it as new, but it really follows a trend that we've been working on for a while and talking about of moving from just imagery to videos and then to interactive videos.

So for the last couple of quarters, we talked there's been enormous increase in the amount of video consumption. That's reflected in the amount of time people are spending watching videos. It's reflected in a disproportionate contribution to ad revenue. I mean we think that Story Pins are the next step in that evolution.

So letting people have a closed loop where they can publish directly onto the platform, they can engage users, not about entertainment, but about their interests, and those users can contribute back and can build more of a community around that media. We think that's something that's different. It's not really a need that's met in the market in the same way that Pinterest is approaching it.

And so while we don't forecast that into growth because it's early days, we think long term, it's something that's going to really improve the growth and the engagement on the platform.

And Justin, on the expense side, I'll break that down a little bit. I think there's a question in there about the charitable contribution and how that would be treated and then how we're thinking about OpEx versus cost of revenue. As a reminder, cost of revenue scales with our user growth and product complexity. So that's more tied to our user growth forecast and tends to be disconnected from revenue performance. It's much more seasonal than our user growth.

What I was referring to was non-GAAP OpEx growth. We've excluded the charitable contribution from that. We included it in our GAAP results but excluded it from non-GAAP in order to provide more clarity around the trends and the operating investments we're making in the business. So when we talked about mid-teens growth sequentially in OpEx, I was referring to non-GAAP OpEx, stripping out the impact of the $20 million charitable contribution that we reported last quarter.

What that reflects is it reflects an increase in the year-over-year growth rate in headcount from where we were last quarter at 17%. And then we're going to, as we mentioned, start to roll out comprehensive marketing campaigns for the first time later in Q2.

Our next question comes from the line of Rich Greenfield from LightShed Partners.

I got two. Ben, I think when you were talking earlier about Story Pins and opening it up to more creators, curious, could you give us a sense if you were looking at sort of end of Q1 or even where you are today versus where you were in Q4? How many people are now have Story Pins available to them? And what is it doing? Like, can you give us any sense of like as users are engaging with Story Pins, what it means to either time spent monetization or both?

And then sort of just a bigger picture for both you and Todd. As you think about sort of connecting brands with creators, you're certainly giving creators more of a way to be on the platform and to create unique content, wondering, as you look at sort of the ad units, you're seeing -- we're seeing more and more video throughout Pinterest, but a lot of them are sort of what I would call video ads you could see elsewhere on the Internet. How do you start to begin to get brands to actually work with kind of native Pinterest creators so that ad units feel more natively Pinterest and something really unique to Pinterest versus just video that could be anywhere? I'd be curious on your thoughts on both of those.

Yes. Thanks for the question, Rich. So the first part of your question is kind of where are we in the rollout of Story Pins on the creator side and on the audience side and what do we know about its impact on things like time spend and monetization. And briefly, we're still in pretty early days. So the number of Story Pins has increased substantially across Q1. It roughly doubled quarter-over-quarter, but it was off a small base.

And just to give a little bit of visibility, we've started small, and we're expanding slowly for 2 reasons. The first is that a lot of what Pinterest brand is anchored in is positivity, and so we wanted to set a really high bar for the content safety and set the tone for what the platform is. So when you look at things like the creator code, which was our norms and guidelines for what kind of content creators have to agree to before they publish content, even to the examples of the types of Story Pins that we're promoting and talking about, they're really trying to set the tone for the future. And that tone is around positivity, but it's also around actionability, small ideas that might be used again and again, things like how to make a breakfast or how to reorganize your kitchen, things that can actually build a library of useful content.

The second reason that we started a little bit smaller, although we're now preparing to expand that more broadly, is that we're really trying to build a new supply/demand marketplace inside of Pinterest. So today, when you use Pinterest, we recommend content, and we have done so for years without the need to follow or subscribe to anyone. We take a look at what you pinned, what you've saved and we recommend things to you in the future. And that's a pretty optimized system. With Story Pins, we're taking a small group of high-quality creators, and we're asking to publish and they were teaching users how to follow, so they see more. So I think it's a little bit too early to say with confidence exactly what we're seeing in time spent and monetization.

That said, we are doing it because we think it's going to make the service more engaging and more useful over the long term. We think there's a good market precedent for that, and we really are encouraged by the early signs. I just don't want to too early to come out and have people kind of modeling based on such a least set of data.

I think your second question really was about how does that translate into more native ad experiences, and I'll let Todd sort of add anything to it, but we're already seeing examples of where brands and creators are teaming up to create a really useful and inspiring image. So one example is Toyota, who partnered with creators, to show the types of people that have mini vans, how they fit into their lives and kind of paint a really realistic picture versus kind of a veneered kind of entertainment-based picture that they might be able to experience in other platforms. And the response from Toyota and their brand managers was really great in terms of brand perception and favorability consideration. And so that's an example. We provided some other examples in our last earnings call, but we do think there's a great opportunity both by kind of matching people up in the market and then by building new tools, which may let creators more directly share products and services they love with their audiences.

Are those things you would expect to roll out throughout '21, those types of tools you're talking about?

I think that you'll see different ways for creators to engage directly with Pinners throughout the year. Yes.

Your next question comes from the line of Douglas Anmuth from JPMorgan.

I just wanted to revisit some of your earlier comments just on the U.S. You talked about in mid-March just the easing of restrictions, how you saw slower U.S. MAU growth and lowered engagement. I was just curious there. Did that reflect as well in terms of U.S. revenue growth? Or was there a point in Ross' earlier question just that it's fairly disconnected -- revenue growth is fairly disconnected right now from users in the engagement just given the higher pricing that you're seeing?

Yes. I mean I understand the question. We talked about them as being fairly different phenomena. I think we had a little bit of unwinding toward the end of March as people started to go outside from a monthly active user and engagement perspective. But I think Ben spoke before, a lot of our shopping orient engagement was very resilient. So that -- yes, I don't want that to be misunderstood.

We had like a remarkable increase in the number of Pinners engaging with shopping surfaces. Our product searches were up twentyfold, and so that's something not to dismiss. And we doubled our attributed conversions in the quarter as well, which speaks to some of that lower funnel behavior.

But given the upside we have in terms of our product investments, all the automation work we've done, the upside in our sales coverage and diversifying into the mid-market, and in addition, internationally, continuing to roll out, that has been a lot of upside. So we were actually -- I think we're -- we ended up increasing our ad impressions 22% globally in the quarter, and our effective CPMs or realized pricing was up 46%, just to give you a sense globally of how that happened. And our ad load was actually down on a year-over-year basis in the U.S. and globally, which is a pretty interesting fact to consider when you think about that question that you posed.

Okay. That's helpful. And just a follow-up. I mean I would suggest, obviously, higher ROI. But I guess are you seeing kind of the increases in auction density that you've been looking for as you build out the number of advertisers on the platform?

We are definitely seeing benefits from advertiser diversification in a number of ways. I think it starts, Doug, with one the things we've talked about for the last couple of years. We really want ads to feel increasingly like content to our users because of the mindset that they bring. And by diversifying our advertiser base across verticals and into the mid-market, we've been increasingly able to do that. And so I think that's kind of where it starts, but we've also seen benefits when it comes to auction density. But I would point again to more efficient use of our monetizable supply built against that commercial mindset and planning behavior that our users bring. That's the biggest driver of our performance.

This will be our last question, Colin Sebastian from Baird.

I have a couple of questions as well. I guess, first off, I was hoping you could expand a bit on the growth in the Gen Z and the platform, their activity, which you've highlighted a couple of times in the call, if there's any context, additional context around how much that group now represents of users or activity. Or where are you seeing as an offset less engagement, which cohorts or which generations?

And then outside of your comments on recent user trends, I just wanted to follow up on advertiser activity. I think, Todd, you're making the point that you're seeing strong growth or engagement with advertisers in spite of some of the sequential trends in users. I just want to clarify that because I know that question has been coming up.

Sure, Colin. So starting with Gen Z, we've mentioned for a few quarters in a row that we're seeing continued growth, and they're growing part of our user base, but we're far from being penetrated entirely. They do have slightly different Pinterest categories than our historical user base. So there's overrepresentation of interest in art, entertainment, women's fashion. There's less of a pronounced interest in things like home decor. They tend to be more engaged with native content relative to our historical cohorts, things like video. They are some of the early adopters of products like Story Pins. They tend to have a higher activation rate and they end at a higher retention rate. So those are a few of the trends that we're observing with that group of users. We haven't yet started building features that cater to them specifically, but we're excited to see how they use the platform, learn how we can serve them better while still making sure that we're consistent with our overall mission of bringing people inspiration to create a life they love.

And then Colin on the advertiser activity, I'll try again on this one maybe from a different perspective or angle. It's probably -- I don't know if the question is really around the 78% growth we posted this quarter versus 70%. I think it was 76% in Q4 with a slightly easier end of quarter comp, but it's worth just remembering where we were in Q4. We had a longer shopping season. It was -- started earlier and ended longer, so it was a big shopping season for us. And then we had unusually strong election year-driven social media avoidance on other platforms that we benefited from that receded a bit in Q1. But I thought our performance was exceptionally strong on a global basis, and the team executed really well across product and go to market.

And where we're seeing that in terms of one way of thinking about it in terms of advertiser activity is that our number of joint business partnerships, which are indications of intent to spend, the number of joint business partnerships doubled year-to-date versus last year. So that's an indicator of how we're thinking about the advertising demand. Does that help?

Yes, it does help. I think the question is also related to if user trends are flattening sequentially or down sequentially, is there a risk that advertisers will follow that sort of looking out versus what their activity is right now?

Well, I think if you look back over the last couple of years, we've been on a steady upward trend. We think we grew -- if you strip away the impact from what we think, we're probably some pulled forward users last year into the COVID period. We're still up north of 6% in the U.S., compounded over the last couple of years, and so that -- and that's been relatively consistent with the longer-term trend in terms of users. And I think the investments we're making in the shopping experience and a more compelling user experience in these new formats around the native content ecosystem are going to be really exciting for advertisers to participate in.

I think that ends our call for today. That was our last question, and so we're ready to close it out. Thanks so much, everyone. We'll see you next quarter.

Thanks again to all of you for joining the call and for your questions. We'll keep the dialogue going. Until then, we just hope everyone stays safe, takes care of themselves. Enjoy the rest of your day.

Thank you again for participating. This concludes today's conference call. You may now disconnect.