More than 4bn of the 16bn that was locked up in SSIAs has already been paid out as these accounts mature.

But according to Davy Stockbrokers, all of the evidence suggests that as much as 85% of the money is still sitting on deposit. Banking analysts Scott Rankin and Emer Lang believe that storm clouds on the horizon are causing people to be more careful with their money.

"While it is too early to say, it would appear that the early predictions of a spending bonanza, at least in 2006, will provide wide of the mark, " they said. "We have cut our forecast for consumer spending growth this year from 7.5% to 6.5%, partly because of higher inflation but also because we think rising interest rates are prompting many people to be a bit more cautious."

The two analysts believe that, even when savers raid their SSIAs, it is unlikely the money will disappear on conspicuous consumption.

"From our discussions with banks, it seems that with three months of data available, perhaps 85% of deposits have rolled over, a very low single-digit percentage has been used to pay down debt, and a good portion of the rest that has been withdrawn will probably be reinvested."