Facebook saw an unexpected slump in users this Christmas in the UK, with 600,000 social network visitors switching off.
The dip - a fall of 1.6%, according to monitoring firm Socialbakers - made Britain the only country among Facebook's top 10 territories where usage dropped.
Monitoring firm SocialBakers said that Britain is the sixth most active country on the social network, with 33 million users.
Responding to a Guardian article, the monitoring firm said that the 'fall' in numbers could be caused by the fact that Britain is nearly at "full penetration" in terms of Facebook users - with 52.65% of the population using the network.
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The firm points out that more than half of the population are on Facebook, while 15% are under 13 and not allowed on Facebook.
A further 16.5% of people in UK are older than 65 and "typically not on Facebook" according to SocialBakers figures. Only 4% of 65+ year olds are on Facebook in the UK.
"I can't imagine their fans could grow by 10–20M new users, although this depends if they allow teens under 13 on the platform and furthermore largely depends on their mobile adoption," the firm said in a statement.
"The numbers are from Facebook’s ad interface, and Facebook unlike other companies, updates this data on a pretty regular basis. No other company does that – they give you rough estimations on an irregular basis, which is not enough in todays moving social marketing world."
"The monthly active user count is statistically vulnerable to more casual users of the platform, users that don't use it that often and might fall out of the 30-day range from time to time. And yeah, my grandpa might sometimes not be an active user on Facebook, even though he is using it."