When Snap went public in March—in one of the most eagerly anticipated tech IPOs in recent memory—some analysts expressed concern about a slowdown in the growth of its Snapchat messaging app.
Now, a new number suggests those concerns may have been well founded.
In a note to Nomura Instinet's invesment clients on Wednesday, Snap analyst Anthony DiClemente says statistics from SensorTower, a company tracking the popularity of mobile apps, show downloads of Snapchat have fallen by 22% in the last two months.
Downloads on Apple's iOS platform have been even worse, declining by more than 40% in the first two months of the second quarter.
By comparison, downloads of Facebook-owned Instagram have shown year-over-year growth, DiClemente says, "suggesting that competitive pressures may be intensifying for Snap, challenging the platform's ability to attract and retain new users."
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The analyst has a "reduce" rating on the stock and a $14 price target, adding he has lowered both his revenue and profit estimates for this year and next year.
Snap's stock (snap) traded as high as $27 after it went public, giving the company a market value of $18 billion, but it has fallen sharply since. Its share price dropped by another 6% on Thursday to trade in the $18 range, not far from its IPO price of $17.
Much of the pressure on Snap's shares stems from concerns that Instagram is eating into the company's user growth, and taking away advertisers as well.
Instagram added a feature called Stories earlier this year, which allows users to add multiple photos and videos to create a collection with a specific theme. The feature is essentially a carbon copy of a Snapchat feature with the same name.
Instagram said earlier this year that more than 200 million people use its Stories feature every day, which is more than Snapchat's entire user base of 161 million.
Snap and its defenders argue that Snapchat functions differently from Instagram because it is much more focused on sharing among individuals, whereas Instagram has more of a public broadcast model, in which users track how many likes and comments they get.
According to a recent survey by App Annie, another app analytics company, about 35% of Snapchat’s daily users in the U.S. aren’t on Facebook the same day they use the app, and more than 45% can’t be found on Instagram on the same day they use Snapchat.
The risk for Snap is that while Snapchat's model may be more appealing to users, Instagram's model may actually turn out to be more interesting to advertisers.