The temperature in Lea Wait’s home has been falling along with stock prices.

Wait, 61, invested the early retirement buyout she took from AT&T Corp. in 1998. As stocks gyrated this winter and the heating bill at her Maine home climbed to $600 a month, she made new investments: Thermal underwear and a wood stove that burns “BioBricks” made of condensed sawdust and wood chips.

Rising food and fuel prices, falling interest rates and screeching declines in worldwide stock markets have Wait and thousands of other retirees paring spending to levels some haven’t seen in decades, forgoing dinners out, cutting back on groceries and canceling plans to visit grandchildren.

“All these costs are added up but when I get my Social Security check, it’s the same thing,” said Johanna Walker, 75, of Greenfield, Wis., a retired receptionist who said she depends on Social Security.

As a group, retirees are wealthy. People 65 and older have an aggregate net worth – assets such as homes, cars, stocks and savings accounts minus liabilities such as debts – of $14.45 trillion. That’s more than one-quarter of the nation’s total personal net worth, according to an analysis of the most recent data from the Federal Reserve-sponsored Survey of Consumer Finances.

But the median income of people 65 and older in 2006 was $16,443, according to the Employee Benefit Research Institute, an independent nonprofit group.

Social Security accounted for roughly 40 percent of average income for people 65 and older, according to the institute, while wages and salary earned by those who kept working were about a quarter of average income. The rest came from pensions, annuities and assets.

Financial advisers say retirees with assets should spend, as a general rule, only 4 percent of their investments each year in retirement. But larger outlays are sometimes unavoidable.

Ed Block, 81, has seen a series of expenses drain his savings in the 22 years since he retired. He and his wife helped with two granddaughters’ college bills and still contribute to one grandson’s prep school expenses. They’ve started a college fund for the rest of their grandchildren, assisted two sons who were downsized and pitched in when a grandchild needed special education.

“Twenty-two years without a paycheck is a very long time in the face of persistently rising costs,” he said.