Facebook posts $3.89bn quarterly profit, up 71% from last year

Shares hit record high after figure is much higher than expected, with total revenue climbing 44.8% thanks to increased mobile video ad sales

Facebook has delivered a much higher-than-expected quarterly profit, driven by a sharp increase in sales of mobile video ads, sending its shares to an all-time high.

Total revenue rose 44.8% to $9.32bn from the same period in 2016, of which Facebook posted a profit of $3.89bn - up a whopping 71% from the year before.