The value of sport to the UK economy in 2008 had grown to £17.38 billion with 441,000 jobs. The figures for the south west region are £1,606 million and 44,000 jobs, so roughly 10% of the total.
These financial exercises don't claim to be exact, but they do show trends and these figures demonstrate an increase in the spend and in the numbers of people employed.
A lot of the money is in the things surrounding sport, the clothes, equipment or going to events. The breakdown for the total expenditure showed that 22% was spent on subs and fees and 19% for clothing and footwear while 15% was for gambling and 10% for TV.
So at least 25% of the total is for watching sport, probably while wearing sports gear.