Facebook has updated its IPO filing, with one addition being a stat that’s sure to be quoted lots in the coming months. The social network says that its users racked up 10.5bn minutes a day on the site in January this year. What’s more, that’s purely for the website – the figure doesn’t include people logging into Facebook from their mobile phones or tablets. “Aggregate minutes per day increased 57% and average minutes per user per day increased 14% during January 2012 as compared to January 2011,” explains the filing. File this alongside other recent big numbers from Facebook: it has 845m monthly active users – meaning an average of 12.4 minutes a day for each user – with 432m people accessing Facebook from a mobile device.