Twitter posted better-than-expected quarterly revenue and a surprise increase in monthly users, sending shares up almost 16% to a nine-month high as its campaign to clean up fake and abusive accounts continued to attract advertisers.

Twitter shares plunged by nearly 12% yesterday after the social media giant reported a yearly increase in active users but lower advertising revenue.

Facebook’s stock has fallen well below its $38 IPO price in the social network’s second day of trading as a public company.