The social media brand, which was acquired by Facebook for $1 billion in 2012, only opened up its advertising program in September. While 200,000 advertisers isn’t much compared to its parent company Facebook, which has two million active advertisers, it’s still an impressive jump for the newcomer to social media advertising. Instagram says 75% of its advertisers are now from outside of the United States.

For a basis of comparison, Twitter has just over 100,000 advertisers.

With 400 million users, Instagram is growing up and drawing advertiser dollars, according to reports. Facebook hasn’t yet released any numbers about how much revenue Instagram’s ads are bringing in, but analyst estimates indicated that it would be a massive business already. Credit Suisse estimated that Instagram’s ad business brought in $730 million in revenue for the fourth quarter of 2015, projecting $3.2 billion in revenue this year. By 2017, Credit Suisse predicts Instagram will be a $5.3 billion business.

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Instagram’s relative success thus far as an advertiser could be credited to its role as a discovery platform, according to the company. In a recent user survey, 60% of users said they learn about products and services on Instagram, and 75% of respondents said they take some sort of action, such as visiting a website or shopping after being inspired by an Instagram post.

As it improves ad targeting, Instagram’s revenue is likely to grow even further. As Facebook’s COO Sheryl Sandberg said a few weeks ago at the Goldman Sachs Technology and Internet Conference, Facebook is actively working on improving targeted and ad relevance on Instagram.