Depressed? It may not help you to know this, but you are not on your own. According to an academic, the most depressing day of the year falls on a Monday in January - so-called 'Blue Monday'. The actual Monday varies between individuals depending on a number of factors such as the number of days since christmas, level of debt and how long since your new years resolution was broken.

The hypothesis was put forward by psychologist Cliff Arnall, who was at the time a tutor at the Centre for Lifelong Learning, a Further Education centre attached to Cardiff University. He even proposed an algebraic formula for it.