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+---- Thread: Blue Monday formula (/showthread.php?tid=849)
Blue Monday formula - mklabgr - 07-04-2026
![[Image: 6cbe5fc08ae0e9e3e314600fdfb591f18ada6fab]](https://wikimedia.org/api/rest_v1/media/math/render/svg/6cbe5fc08ae0e9e3e314600fdfb591f18ada6fab)
Blue Monday formula
Summary
"Blue Monday" sounds like a profound psychological phenomenon, but it actually started as a clever marketing stunt by a British travel agency in 2005 to get people to buy summer vacations. To make it look official, they hired tutor Cliff Arnall to craft a mathematical equation that calculates the exact "most depressing day of the year"—usually landing on the third Monday in January.
The formula blends very real, relatable human struggles—like cold, dreary weather ($W$), tracking the mounting post-holiday debt ($D$) against your next paycheck ($d$), realizing you've already abandoned your New Year's resolutions ($Q$), and feeling a profound lack of motivation ($M$).
While scientists and mental health groups quickly dismissed the formula as complete nonsense since you can't actually quantify a bad mood with algebra, the concept stuck with us anyway because it perfectly captures that very real, deeply human feeling of the mid-winter slump when we are all just exhausted, broke, and desperately wishing for spring.
ARTICLE