Blue Monday (date) Blue Monday (date) Blue Monday is a name given to a day in January (typically the third Monday of the month) claimed 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. It takes into account weather conditions and thus only applies to the Northern Hemisphere. The idea is considered pseudoscience, with its formula derided by scientists as nonsensical. This date was published in a press release under the name of Cliff Arnall, at
Determination of the day of the week method have failed to point out his error, most notably Martin Gardner. In 1752, the British Empire abandoned its use of the Old Style Julian calendar upon adopting the Gregorian calendar, which has become today's standard in most countries of the world. For more background, see Old Style and New Style dates. In the C language expressions below, y, m and d are, respectively, integer variables representing the year (e.g., 1988), month (1-12) and day of the month (1-31). In 1990, Michael Keith and Tom Craver published the foregoing expression that seeks to minimise the number of keystrokes needed to