
Back in 2005 a travel company created a campaign around the idea of "Blue Monday". Scheduled to fall on the third Monday of January, the company labeled this date as the most depressing day of the year, thanks to a combination of cold weather, short days and the post-holiday comedown.
The evidence for Blue Monday is a bit thin, but it’s certainly not unusual to feel down around this time—especially if you live in the Northern Hemisphere, where January can feel like a very dark, dreary month.