Instagram Stories has 500m daily users

"Roughly half of Instagram’s  1 billion users now use Instagram Stories every day. That 500 million daily user count is up from 400 million in June 2018. 2 million advertisers are now buying Stories ads across Facebook’s properties.
CEO Mark Zuckerberg called Stories the last big game-changing feature from Facebook,  but after concentrating on security last year, it plans to ship more products that make “major improvements” in people’s lives."
Source:  Techcrunch, 30th January 2019