But a British psychologist has gone one step further, designating today, Monday January 24th, as the worst day of the year.

Dr Cliff Arnalls, a specialist in seasonal disorders, came up with the theory after using his own unique formula incorporating factors as diverse as weather, debt, fading Christmas memories, failed resolutions and a lack of motivation.

For the mathematically minded, the exact make up of his formula of misery reads 1/8W+(D-d) 3/8xTQ MxNA.

Where W is weather, D is debt, minus the money (d) due on January’s pay day and T is the time since Christmas.

Q is the period since the failure to quit a bad habit, M stands for general motivational levels and NA is the need to take action and do something about it.

Dr Arnalls calculated the January 24th was an especially depressive day, coming a whole month after Christmas festivities.

And he also argues the country’s weather plays a significant part in the process.

Although the Winter Solstice, the shortest day of the year, fell on December 21st, he claims Britain’s notorious weather system inevitably bring low, dark clouds to across the country this time of year.

The country’s biggest mental health charity agrees January is gloomy, says up to a third of Britains suffer from seasonal affective disorder, or ‘SAD’, also known as winter depression.

While most cases of the winter blues are not severe, between two and five percent of those with ‘SAD’ can’t function without continuous treatment.

Researchers claim it’s extremely rare to find anyone with the disorder within 30 degrees of the equator, where days are long and the sky is bright year-round.

Britain’s medical profession says anecdotal evidence supports the claim that January is particularly gloomy.

“Yes, we do see lots of people with depression and anxiety in the winter months.” said Royal College of General Practictioners’ spokesman Dr Alan Cohen.

“The message is it’s not a terrible disorder, people do get better,”

The country’s doctors recommend exercise and reading up on depression as the best ways to beat the blues.

The formula was devised to help a travel company “analyse when people book holidays and holiday trends,” said PR spokesman Alex Kennedy.

He claims people are most likely to buy a ticket to paradise when they feel like hell.

“People feel bleak when they have nothing planned, but once they book a holiday they have a goal, they work toward having time off and a relaxing period,” said Mr Kennedy.