HR has been warned that staff will be at their lowest ebb next Monday as 24 January has been identified as the most depressing day of the year.
A formula created by a part-time tutor at Cardiff University shows that foul weather, debts, fading Christmas memories, failed resolutions and a lack of motivation all conspire to make people miserable.
Dr Cliff Arnalls discovered that 24 January was especially dangerous, coming a whole month after the Christmas festivities. Any energy gained from the holiday will have worn off by the third week of January, he said.
The fact that the most depressing day happened to be a Monday was merely a coincidence, he said.
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GPs advise exercise and reading up on depression to beat the blues.