Online analytics firm ComScore released the latest figures Wednesday about how many people are visiting Facebook. The report showed that unique visitors were down in May from April and March, indicating that the site’s growth might be tapering off.

In March, Facebook attracted 158.93 million unique users, a number that fell to 158.69 million in April and 158.01 million in May. However, while fewer people may have visited the site, they’re spending more time surfing Facebook. Reuters reports that users spent an average of 380.3 minutes on the site in May, up from 378.9 minutes in April.

The news service believes that this may be evidence that Facebook’s growth is slowing:

Keeping users coming back — or combating fatigue — is crucial for all social media services, analysts say. Facebook is consistently trotting our new features, including the timeline interface rolled out this year, and more are expected with the deal to acquire popular photo-sharing app Instagram.

Reuters notes that it’s difficult to compare year-to-year statistics, as ComScore recently changed the way it tracks statistics.

Readers: Have any changes made by Facebook caused you to visit the site less frequently?

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