Shares of social media giant Facebook (NASDAQ:FB) are down 5% after the company said it expects revenue growth to slow throughout the rest of this year.

Despite the warning of slowing growth, Facebook reported second-quarter earnings that came in ahead of Wall Street estimates.

Facebook’s earnings per share (EPS) amounted to $3.61 U.S. per share compared to $3.03 U.S. per share expected by analysts. Revenue came in at $29.08 billion U.S. versus $27.89 billion U.S. expected by analysts.

Daily active users of Facebook totaled 1.91 billion in the second quarter, meeting analysts expectations.

Facebook’s revenue grew by 56% year-over-year in the second quarter, the fastest rate of growth for the company since 2016. The company pointed to a 47% rise in the average price per advertisement, along with a 6% increase in the number of ads it delivered in the quarter.

Revenue from Facebook’s “Other” segment, including consumer hardware such as the Oculus virtual reality headset, totaled $497 million U.S., up 36% from a year ago. The company’s free cash flow of $8.51 billion U.S. fell short of the $9.08 billion U.S. analysts had forecast.

With respect to guidance for the second half of the year, Facebook said it expects “year-over-year total revenue growth rates to decelerate significantly on a sequential basis as we lap periods of increasingly strong growth.”

That guidance was effectively unchanged from Facebook’s previous guidance. Analysts had expected $28.22 billion U.S. in revenue for the third quarter, which implies 31% growth.

Separately, Facebook said it will require employees to be vaccinated before entering its U.S. offices. Facebook shares have risen 37% since the start of this year to $373.28 each.