What is it?
Blue Monday is a name given to a day in January (typically the third Monday of the month) reported to be the most depressing day of the year. The concept was first publicised as part of a 2005 press release from holiday company Sky Travel which claimed to have calculated the date using an equation.
The idea is considered pseudoscience, with its formula derided by scientists as nonsensical.
Who invented it?
This date was calculated by Cliff Arnall, a tutor at Cardiff University, and it takes into account many factors, including: weather conditions, debt level (the difference between debt accumulated and our ability to pay), time since Christmas, time since failing our new year’s resolutions, low motivational levels and feeling of a need to take action.
The happiest day
On the contrary, the happiest day of the year usually falls in the summer, at the end of June.