The social network’s share price fell by 1% to $8.80, with its earnings per share falling to $0.14.
Xiaomi’s earnings per unit fell by 0.1% to 2.9 cents per share.
Facebook’s earnings fell by 3% to 13 cents per unit, and Google’s dropped by 2% to 8 cents per shares.
The stock fell in the US, but has rallied in the rest of the world.
Facebook is the biggest shareholder of WhatsApp, which is owned by Facebook.
WhatsApp was bought by Facebook in 2014 for $19bn, with WhatsApp users now having the option to use its services without having to log in to their Facebook accounts.
The US is the company’s biggest market.
Xiaomi shares closed at $8,806 on Monday.
Facebook shares closed down 1% at $11,824.
Twitter shares closed up 1% with a 0.6% gain.
Google shares dropped 1% and Microsoft shares fell 1%.