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Last Updated: Monday, 27 March 2006, 15:27 GMT 16:27 UK
What else happens when clocks go forward?
WHO, WHAT, WHY?
The Magazine answers...

Not only time changes
The clocks went forward on Sunday and the nation lost an hour's sleep but what are the consequences?

The UK is now officially in British Summer Time and the nation's punishment for lighter evenings was an hour's less sleep over Saturday night and Sunday morning.

But what is the impact of this loss, apart from a making people a bit more tired and the time spent resetting watches, central heating boilers, videos, DVD players and radio alarms.

According to several studies when the clocks go forward there is a rise in accidents on the nation's roads for a few days and the stock market slumps.

Sleep deprivation

Losing an hour's sleep affects people's body clocks - the internal circadian rhythms that regulate our sleep-wake cycle - and it can take days to recover.

The tiredness caused when our body clocks are out of sync can have serious repercussions and the more sleep deprived a person is the worse they feel.

Studies by the Sleep Research Laboratory at Loughborough University, have found that road traffic accidents increase slightly in the days after the clocks go forward.

There is also an increase in accidents when clocks go back in the winter, which is thought to occur because people use the extra hour they gain to stay up later, making them more tired.

WHO, WHAT, WHY?
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The stock market also has a habit of falling when the clocks go forward, according to Investor Profit.com. The FTSE 100 has fallen 15 years out of the last 25, with an average loss of 0.77%.

It says the likely reason for this is the spring clock change comes when the end of a trading quarter and the financial year is approaching, which has an effect on what is bought and sold.

The stock market has risen in 17 of the last 25 years on the day after the clocks go back at the end of October.

Dusk or dawn?

On the more positive side energy consumption drops for a few days, as does the crime rate.

A US study found that 300,000 barrels of oil were saved every day after the date for clocks going forward was itself brought forward by a month.

Studies have also shown that crime rates dip for a few days after clocks are changed for spring, as criminals have to readjust to the lighter evenings.

Recent British Crime Surveys have shown that over half of criminal offences take place when it is dark in the late afternoon or evening.

Offences occurring in conditions of semi-darkness are far more likely to occur at dusk rather than dawn, suggesting that lighter evenings reduce the risk of crime rather than lighter mornings.

However, the Home Office says definite conclusions are difficult to draw as regards the effect of darkness on overall levels of crime.


Your comments

Hasn't it occurred to anyone that the increase in road accidents might be due to people adjusting the clocks on the dashboard of their cars?!
Spook6, Vienna, Austria

Well, I lost an hour of my birthday! Friends have kindly offered me an hour birthday party in October so I can claim it back.
h, Durham

The state sanctioned screwing up of the entire population's body clocks twice a year is ludicrous. It's the same every year - I've just about recovered from the constant tiredness brought on by the dark winter mornings, when I'm knocked back by the time change. I have no hope of resetting my body clock until I've managed to reset those of my children. I'm likely to be tired for the next couple of weeks. All so we can have an extra hour of daylight in the evenings. I hate that as well, I'd really like to be able to see the stars on a summer evening without having to stay up too late.
Danny, Bristol, UK

I have always thought the changing of the clocks a crazy idea. The Province of Saskatchewan does not bother with Spring ahead & Fall back craziness. Why not readjust it to either GMT or BST & leave it alone permanently?Would save a lot of aggravation & road accidentsaround the world,as new statistics come to light
C.Smith, burlinton ,canada

What about the effect on people on medication? I take tablets for Diabetes and the movement (both ways) disrupts that but it is worse for those on Insulin. The same must apply to most other people on regular medication.
Danielle Branch, South Oxhey. Herts

After all these years exactly what is the point of messing about with the clocks twice a year? You can't tell me it's for the farmers - the cows can't tell the time, business doesn't benefit one jot I'm sure and the school kids are at more risk on their way home in the winter. So what is the point?
Harvey, Nottingham

You'd think one hour wouldn't make that much of a difference and to my husband and I it didn't. It was a different story with our baby daughter though. Just one hour and her eating and napping schedule was totally thrown out, she was grumpy the whole of Sunday, and found it very difficult to fall asleep at her usual bedtime. I guess to little people, their hours seem a lot longer than ours.
Kirsten, The Netherlands

Why does British Summer Time run from March to October - when we all know the British Summer only lasts for three days at the end of May?!
Becky Lewis, Chelmsford

My two year old daughter took it all in her stride - my wife and I were woken up before 7 this morning with cries of "It's waking up time". Ugh.
Tom K, London, UK

What a load of old rubbish! No doubt this "research" was paid for by the campaign for not changing our clocks twice a year! Does anyone seriously want it to be dark until 9am in winter? Or perhaps lose an hour of our long Summer evenings? I like my lighter winter mornings and my long Summer evenings thank you very much!
Gareth, Scunthorpe

When we put the clocks forward it should be done at 9am on the Monday morning, when they go back it should be at 6pm on a Monday evening that way e get the benefits without it appearing to impact negatively on us - ie we would lose an hours work rather than sleep!! and gain an hour of the weekend!!
kevin, milton keynes

I have a low blood sugar and have to take meals at regular times. I can make some allowance at home but at work I have to take my lunch break at the appointed time. Changing the clocks twice a year is one big pain in the neck - or in my case the head as messing around with meal times just gives me a migraine. And for what? The farmers? Farmers will make the best use of daylight hours regardless of what time the clock says it is. So come government, do something about it.
Chris, Sheffield, UK

I used to think that the clocks going forward and back was a stupid idea too until I discovered that it is done to save energy. The change to BST saves fossil fuels used to light and heat and so saves homes and businesses millions and is also better for the environment. I don't have any problems with it now.
Steve Phillips, Sheffield

I agree with most of the above comments. Why don't we just stick to GMT? I really resent the thought of Old Father Time joyriding around all Summer on my hour. Give it back, you old bounder!!
Richard Price, manchester, England

Contrary to other comments, thank heavens for change!. I'm constantly amazed by how the week leading up to the clocks changing my childrens wake up time reflects the need for the clocks to change. Last week they started wanting to get up at 6.30am, whereas they normally get up at around 7.15am. By Tuesday my body clock will be back to normal and I'll be very thankful for the extra hour in bed in the morning.
Mike Wallace, London

We lose an hour in March and don't get it back until October. This is like a 7 month loan of our time and should thus be re-paid with interest. Therefore should we not get (say) an hour and five minutes back in October?
Chris Stocks, Chesham, Bucks

Feel sorry for the people on shift work that get paid an hour less because of it. Mind you, they get it back later in the year...
Mike H, Nottingham, UK




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