https://www.cnbc.com/2018/07/26/facebook-on-pace-for-biggest-one-day-loss-in-value-for-any-company-sin.html

Facebook was on track Thursday to post the largest one-day loss in market value by any company in U.S. stock-market history after releasing a disastrous quarterly report.

Through midday Eastern Time, the social media giant's market capitalization had plummeted by about $120 billion to about $508 billion as its stock price fell by more than 19 percent. At Wednesday's close, Facebook's market cap had totaled nearly $630 billion, according to FactSet.