Answer: Wednesday

In 2009, researchers at Vermont University analyzed the posts of 2.4 million users on Twitter and other blogging services. The researchers focused on word selection and the day of the week the words were used in an effort to determine which day of the week the social media users were happiest and which days they were most miserable.

Although it would be easy to assume that Monday was the most miserable day of the week given that the weekend has just ended and the drudgery of the work week has resumed, the researchers found that Monday was actually a moderately happy day. The high points of Saturday and Sunday offered a sort of protective umbrella for Mondays wherein people were still happy about their weekend.

The darkest day of the week? Wednesday. The glow of the previous weekend’s fun has dimmed and the upcoming weekend seems far away (by Thursday, and more so on Friday, the anticipation of the upcoming weekend boosts spirits). So the next time you find yourself down in the dumps on Wednesday, cheer up, throw your mind to the upcoming weekend, and remember: if you complain about it on Twitter, there’s a good chance you’ll end up a data point in a happiness study.