Asda has been running an Income Tracker since the autumn of 2008. The research for it is carried out by the Centre for Economics and Business Research. The tracker is published every month and the one for October (presumably using September's figures) is now out on line (Thanks to Richard Murphy for drawing attention to it)
One of the thinks the Tracker does is divide households by income in quintiles (20% intervals) and estimate how much spare money the households will have each month after all their essentials are paid for, it's called 'discretionary income.
Discretionary Income is what is left after taxation, groceries, electricity, gas, transport costs and mortgage interest payments or rent. Obviously Asda is very interested in this because it sells a wide range of goods as well as groceries and it wants to know how big the potential market for these might be.
So, in the latest release the bottom quintile has a monthly 'discretionary Income (DI) of minus £76. The next quintile has DI of £11, the third quintile has DI of £93, the fourth has £295 and the fifth has £940. So 60% of UK households are either unable to cover all essential costs each week or are close, or very close. to it. 60% have just over £5,000 a year, or less to spend on holidays, entertainment, replacing a large item of household equipment, savings...
Has anyone noticed the huge jump between the fourth and fifth quintiles? 
The question that needs asking is how much do the budget measures which are supposed to address the cost of living crisis actually mean for the first three quintiles? Clearly they will do little for the 1st quintile, who have a DI deficit of nearly £4,000 a year.