Just wondering where you got your information from?
my own gut feeling initially, but 2 minutes on google got me the Guardian from 2012 and an OFWAT report October 2012:
From the Guardian, May 2012:
Don't be too impressed with the water companies when they say they have been working hard to plug the holes in their pipes. I wrote my first news article about water leaks back in 1980 for a long-forgotten magazine called Municipal Engineering. A study published then – I still have it – put the national water leakage rate at 24%. And nothing has changed. The latest statistics for the four biggest English water utilities show Severn Trent losing 27%, Thames Water and United Utilities (supplier to northwest England) 26%, and Yorkshire Water 25%. In the case of Thames Water, which serves drought-plagued London, that is almost 200 litres, per customer, per day.
Ofwat, ever the industry's apologist, claims leaks have been cut substantially since the mid-1990s. Which is true – but they rose before that, during and after privatisation of the old water authorities in 1989. And recorded losses today are marginally high than they were a decade ago – about 3.4 billion litres a day. That would fill quite a few hosepipes.
I wouldn’t be so naïve as to expect a newspaper to have facts, but it is backed up by OFWAT’s own commissioned report here: http://www.ofwat.gov.uk/sustainability/waterresources/leakage/
This October 2012 report suggests that whilst leak rates were getting better through the early 2000’s, by 2009 they’d fallen back to where they were 10 years earlier.
Briefly, to paraphrase, there's a formula to work out if it's worth fixing leaks, most water companies usually have no supply issues so don't even bother doing the formula.
Whilst not bothering to calculate your leak rate contradicts the 'evidence' in the newspaper that quotes per centages, for the purposes of a footy chatroom, it must be sufficient evidence.
Plus, I drive around a lot and for the last 2 years everything has either been very green or under water.