A continuing drop in users, along with an expected hike in operating expenses, put a damper on Twitter’s generally upbeat fourth-quarter earnings report.

The company reported a 24 percent rise in overall revenues to $909 million, and a 23 percent spike in ad sales, which hit $791 million.


However, total monthly users for the social media giant were 321 million for the quarter, down from 326 million in Q3 and 330 million in Q4 2017.

Combined with the company’s forecast of increased operating expenditures for 2019, the report of the lower user numbers resulted in an eight percent dip in its share price before the market opened on Feb. 7.

Twitter places the blame for both the increased expenses and the user drop on the same thing: its efforts to crack down on rogue users. “In 2019 we will take a more proactive approach to reducing abuse and its effects on Twitter,” the company told investors.

Twitter also plans to change the way it counts users in what it says is an effort to better reflect the number of users whose activity results in revenue. It is now counting what it calls “monetizable daily active users”—only those who use Twitter’s website or app to access its services.