By Ben Richardson BBC News business reporter

Big earnings are the present under the Christmas tree for companies

For many companies it is an opportunity to fill their coffers in a festive boom that can make or break the business year.

According to the British Retail Consortium (BRC) shoppers spent more than �31bn in December last year, with �10bn of that going on gifts alone.

The months of November, December and January can account for as much as 60% of the annual turnover at large retailers, the BRC believes.

Despite a difficult year for the High Street in general, demand seems to have picked up again.

The latest data from researcher SPSL shows shopper numbers in November and at the start of December have increased across the UK from last year.

Old dogs, new tricks

At the same time, consumers have been changing their habits, and the BRC said that people are planning earlier for Christmas, trying to spread the cost over a number of months to avoid taking one big hit in December.

Christmas facts On average, each person will spend �300 on Christmas gifts. The average household will spend �160 on food and drink An estimated 1.7 billion Christmas cards will be sent to friends and family The average Christmas lunch costs �12 per head, without alcohol Children, on average, will get gifts worth more than �250. Consumers will buy �1.2bn-worth of Christmas trees and about 35 million will be grown to cope with demand Britons buy 52 square miles of wrapping paper, enough to cover Hyde Park 33 times over. Source: British Retail Consortium

And instead of fighting their way down High Streets, many consumers are doing their shopping online.

The value of goods bought over the internet topped the �2bn mark for the first time in November, 50% more than a year earlier, analytical firm IMRG said.

In fact, if the number of online shops actually opened up their own bricks and mortar premises, they would create a High Street that was 50 miles long, it said.

One warning, though: the post-Christmas sales could see slimmer discounts than many hope.

The BRC says retailers are being much more canny about ordering and keeping stock, and therefore are unlikely to be left with a lot of unsold goods after Christmas.

Big birds

But while the end of year sales may be under threat, in the lead-up to Christmas shoppers seem less worried about counting the pennies.

Paul Kelly is a turkey farmer from Essex whose family have been rearing and selling the butterball birds since 1971.

Mr Kelly's birds go for about �45 each, about �9 a kilo, many times more than a similar turkey would cost in the supermarket.

Britons eat 40 million turkeys a year

As well as the taste, which he puts down to the fact that his birds are slow-grown from June, Mr Kelly reckons that Christmas is behind the willingness of shoppers to pay over the odds for their dinner-time centrepiece.

"People are willing to trade up," he explained.

"For the rest of the year they are at the mercy of the weekly shop. At Christmas they don't want to scrimp and save."

This consumer urge to splash out also is being seen by cracker company Robin Reed.

"Crackers are such a central part to the day, they sit on the dinner table and people focus on them," said Caroline Nash, the firm's director of sales and marketing.

Splash the cash

The ostentatious nature of Christmas may explain why consumers seem so willing to head for the shops.

One addiction counsellor, who wished to remain anonymous, explained that the holiday period gives people an excuse to do what they normally would not - almost offering carte blanche for a bank balance-busting blow-out.

Average Xmas household spend �160 on food and drink �660 on gifts �20 on cards �20 on crackers �35 on Christmas tree Source: British Retail Consortium

The pleasure, however transitory, of giving and receiving gifts can mark a high point at a dark and cold time of year.

The feel-good factor aside, consumers are no dummies and while they may be willing to pay top dollar, making sure a company gets its slice requires lengthy planning.

To get some of the �160 the average British family spends on their Christmas dinner, Mr Kelly starts mapping out his turkey-breeding schedule almost before the leftovers have gone cold.

West Midlands-based Robin Reed already is designing 2006's cracker ranges, working out what will go inside them and checking to make sure the jokes are not too close to the bone.

Even getting the humble Brussels sprout to the table requires a military-style operation.

Sainsbury's vegetable buyer Russell Crowe explained that sprout pickers are working 24 hours a day in the lead up to Christmas, when as much as 25% of the year's total sales are cashed.