If you live in Sutton and find it hard to drag yourself out of bed in the morning, it's not your fault, it turns out.
A new survey, which has ranked London's boroughs from happiest to saddest based on their tweets, has found Sutton is London's most miserable borough. Enfield comes a close second, with Lewisham not far behind.
Meanwhile, Bexley dwellers are a decidedly more cheerful lot: in fact, it's the happiest borough in London. That's followed by the good people of Haringey, and Redbridge.
The project, which looked at 1.5 million tweets with shared locations over a month, was commissioned by Somerset House for its Big Bang Data exhibition.
The sentiment of the 55,000-odd tweets a day were compared with a list of 2,500 words, which were rated for sentiment from minus five (gloomy) to plus five (chirpy).
The month over which the project ran included Blue Monday, the so-called saddest day of the year. On that day, London's unhappiest tweeters were talking about Celebrity Big Brother (fair), Liverpool Football Club and the death of Davie Bowie. Sob.
Those bucking the trend that day included the City of London, Westminster and Tower Hamlets - the three cheeriest boroughs on Blue Monday.
Meanwhile, throughout the month, the happiest subjects included Christmas, the New Year, and love. Aaaah.
Still - at least miserable Londoners can take solace in the fact that the evenings are becoming lighter and the weather is warming up. It might never happen, guys...