How to live your life by numbers

Whether you're starting an affair or going for a hospital check-up, it pays to take a statistical approach to organising your week. Simon Usborne does the maths

MONDAY

When a Cardiff University maths tutor came up with a formula to predict that 24 January would be the worst day of 2006, few reading the news on Britain's packed commuter trains were surprised to find that it fell on a Monday. And Government figures appear to prove that melancholy peaks on the first day of the working week. A study by the Office for National Statistics showed that from 1993 to 2002, more suicides occurred on a Monday than any other day (16 per cent of the total for men and 17 per cent for women, compared to 13 per cent for both sexes on Saturdays and Sundays).

Two ways to improve your Mondays: avoid job interviews and sushi. Recruitment advisers say employers are more receptive later in the week as the Monday malaise wears off. Interviews held on a Monday are also more likely to be top of the pile, which could narrow the chances of success; one study by the "executive search" industry in the US found that the first person to be interviewed gets the job 17.6 per cent of the time, compared to 56 per cent for the last person.

Fish traders, meanwhile, look forward to a day off on Mondays, when seafood markets traditionally close. That means the average bento box is at best a day old but could have been sitting in the chiller cabinet since Friday.

For retailers who stay open, Monday sees relatively slow trade. But whenever Christmas falls on a Monday (as it did in 2006), one can expect to hear the tills ringing through the festive period. The Centre for Economics and Business Research estimates that from November to December, sales increase 26 per cent when Christmas Day falls on a Monday, but only 21 per cent otherwise.

TUESDAY

Tuesday is probably the day office workers are most likely to shout at their computers, and the busiest day for many IT workers. The second Tuesday of each month is known to tech-heads as "Patch Tuesday", when Microsoft releases its Windows security fixes. The following day is known as "Exploit Wednesday", when hackers pounce to find holes in Microsoft's work. Research by a US internet marketing company suggests that Tuesday is the best day to blog. The website (pheedo.com) found that RSS activity (the web format used to publish frequently updated content) peaks on a Tuesday, increasing the potential number of hits.

Tuesday is also the day to get important jobs done. A study published last month by the US Society of Industrial Psychology said our rational "left" brain dominates thinking early in the week, better for routine, non-social jobs. But after the "miserable Monday" washout, Tuesday heralds the true start to the working week and is the day to refresh a CV or plan a presentation.

WEDNESDAY

Wednesday marks the middle of the week and is also the day for budding romance, according to a survey of 8,000 single people by an online dating site. Forty-one per cent of respondents to the survey by itsjustlunch.com said the best day for a first date is a Wednesday. The reason, apparently, is Thursday. After a successful date both parties get a day's breathing space, but don't have to wait long before a second meeting on Friday night. Alternatively, a "busy" Thursday at work provides a convenient excuse to settle the bill and leave.

Wednesday is also the best day to post online job ads, according to recruitment website, eQuest. com. The site found that 18.1 per cent of activity on its job pages occurred on Wednesdays, compared to 12.3 per cent on Fridays.

Research suggests Wednesday is the best day for sellers to end eBay listings. In an experiment with wrist watches, an online marketing company found that the average selling price in auctions ending on a Wednesday was $113, compared to $67 on a Tuesday and $71 on a Thursday.

THURSDAY

The fourth day of the week is the worst day to be admitted to hospital. A report released last week by the Institute of Public Policy Research found that people who go into hospital on a Thursday stay longer. The 180,000 people admitted on a Thursday in the past year stayed an average 6.3 days, compared to 5.5 days for a Saturday and 5.3 days for a Sunday. The think-tank points to weekend hospital rotas as the main reason; Thursday patients who need just two or three days of treatment are less likely to be discharged during the weekend as staff numbers drop. This "weekend effect" required an extra 500 beds over the year.

If you are planning to publish a novel, bear in mind that book launches are best scheduled for a Thursday. It's late enough in the week for an evening of free champagne to appeal to literary types, but comes before the weekend dash to the countryside.

FRIDAY

Thank God it's Friday - or so they say. The end of the working week should be cause for celebration, but Friday is statistically a bad day. It's also an unlucky day, with superstition peaking on Friday 13th. Unfortunately for so-called paraskevidekatriaphobics (people who fear Friday 13th), the quirks of the Gregorian calendar mean the 13th is more likely to be a Friday than any other day. In a 400-year cycle, the 13th is a Friday 688 times, compared to 684 for a Thursday or Saturday.

But a fear of Fridays is not always irrational. Statistically, it is the worst day to take to the roads. A study published last November by Continental Tyres found that more road accidents happen on Fridays than any other days.

The "fatal Friday" phenomenon is worst in November during the afternoon rush hour, with 2,454 accidents happening between 4 and 5pm (35 per cent more than during the 8 to 9am morning rush hour, and a 10 per cent increase on the same period in October). The report cited various elements as factors, including end-of-week fatigue and heavy traffic, exacerbated by bad weather in November.

Friday is also the worst day for women to start their period, according to a running poll of (presumably) women at MyMonthly Cycles.com. Friday took 43 per cent of votes, followed by Monday with 33 per cent. The "least worst" days were Tuesday and Wednesday, each polling 2 per cent of votes.

The Friday gloom doesn't let up for browbeaten workers. A team of academics at America's George Washington University announced recently that Friday is the best day for bosses to fire employees. One researcher says: "If you tell a person on a Monday that he is going to get the chop, he takes only the negative message. By Friday the words may not be so wounding; in that end-of-the-week reverie, he may even agree that it's best to look for another job."

SATURDAY

If Wednesday is the best day for a first date, then Saturday is the day to tie the knot (unless you're Jewish). Government statistics for England and Wales show that in 2003, 61 per cent of the total 270,109 marriages took place on a Saturday (with only 3 per cent on a Tuesday - the least popular day). Saturdays were especially busy for the Church of England; 87 per cent of its 56,250 weddings were held on a Saturday (with only 0.3 per cent on Tuesdays). But that Saturday share dropped to 50 per cent for the 183,124 civil marriages that took place in 2003. And just 1 per cent of Jewish couples got married on the Sabbath, with the majority (66 per cent) of weddings on Sundays.

SUNDAY

For those not at a Jewish wedding, Sunday could be the best day to hit the supermarket. A recent survey by "field marketing agency" FDS showed that availability of a wide range of products was at it highest (98 per cent) on Sundays. Empty shelves are more likely on Mondays when availability fell to a low of 94 per cent. And despite a recent warning by the UN of a global banana shortage, our favourite fruit (in Britain we eat more than 5 billion every year) was rated the best-stocked line, with 100 per cent availability over a 12-month period.

Sunday is also the day to send fundraising e-mails. A report from eMarketer showed that "open" and "click" rates for e-mails sent on Sundays were highest (if the number of recipients was below 5,000). Just over 30 per cent of recipients opened emails, and 7 per cent went on to "click through". The worst day was on Wednesday with an open rate of 23 per cent and a 3 per cent click rate.