NEW YORK — More than four years after the United States fell into recession, many Americans have resorted to raiding their savings to get them through the stop-start economic recovery.

In an ominous sign for America's economic growth prospects, workers are paring back contributions to college funds and growing numbers are borrowing from their retirement accounts.

Some policymakers worry that a recent spike in credit card usage could mean that people, many of whom are struggling on incomes that have lagged inflation, are taking out new debt just to meet the costs of day-to-day living.

American households "have been spending recently in a way that did not seem in line with income growth. So somehow they've been doing that through perhaps additional credit card usage," Chicago Federal Reserve President Charles Evans said on Friday.

"If they saw future income and employment increasing strongly then that would be reasonable. But I don't see that. So I've been puzzled by this," he said.

After a few years of relative frugality, the amount of money that Americans are saving has fallen back to its lowest level since December 2007 when the recession began. The personal saving rate dipped in November to 3.5 percent, down from 5.1 percent a year earlier, according to the U.S. Commerce Department.

Jeff Fielkow, an executive vice president at a recycling company in Milwaukee, Wisconsin, contributed less to retirement savings and significantly cut back on dining in restaurants and taking vacations in order to keep college savings on track for his two children. "We would love to save more," he said, "but we're doing the best we can."

There have been some signs of a quickening in U.S. economic growth recently after it emerged from recession in mid-2009.

Hiring was stronger than forecast in December and confidence among consumers rose to its highest level in eight months in January.

But many see a long, hard slog ahead and economic growth this year is not expected to be much more than 2.0 percent, barely up from 2011's growth pace.

The big risks include Europe's debt crisis as well as the shaky finances of many Americans, hit by a five-year decline in house prices and still high unemployment. U.S. consumers account for about two thirds of the country's economic output measured by total spending.

Retail sales rose at the weakest pace in seven months in December, according to data published last week.

Sales in 2012 are expected to grow at slower rate than last year, an industry group said on Monday. The National Retail Federation projected sales would rise 3.4 percent this year, compared with than 4.7 percent in 2011.

"When the stock market and the housing market were booming, we saw that a lot of people would take on more debt and save less. They felt the saving was being done for them," said Mark Vitner, managing director and senior economist at Wells Fargo Securities in Charlotte, North Carolina.

"Today, the saving rate is falling out of necessity. Food and energy prices have risen and folks don't have as much money to spend on the things that they would like."

Just as Americans used to borrow against the value of their homes before the property crash, now many are taking out loans from their 401(k) retirement savings plans.

Almost a third of plan participants currently have a loan outstanding, according to an upcoming survey of 150,000 holders of 401(k)s by consulting firm Aon Hewitt.

"People are at a loss, and they are struggling," said Pam Hess, director of retirement research at consulting firm Aon Hewitt.

Loans taken from retirement savings accounts jumped 20 percent last year across all demographics, according to a survey to be published in March. Among lower earners they leapt by as much as 60 percent, said Aon Hewitt's Hess. The vast majority of borrowers, she said, need the money for essential expenses like bills, car repairs and college tuition.

The non-profit Employee Benefit Research Institute's (EBRI) annual retirement confidence survey hit a new low in 2011 with 27 percent of workers saying they're "not at all confident" they'll have enough for a comfortable retirement. Almost 15 percent expect to work until at least the age of 70, up from 11 percent in 2006.

New York real estate broker Leila Yusuf had been very conscientious about saving for retirement, typically socking away $5,000 to $10,000 a year. But her income slid by 30 percent in the last two years as the housing market hit the doldrums and she stopped making contributions.

"I couldn't afford to do it after four deals didn't go through," said Yusuf, 37. "I need money to live on."

In another sign of Americans struggling to make ends meet, EBRI found that more than 20 percent of those aged 50 or older changed their medical prescriptions to save money and almost as many had skipped or postponed doctor appointments for the same reason. Almost 28 percent reported having difficulty paying their monthly bills.

College savings hit
The amount of money Americans put aside for their children's college fees is taking a hit too. Assets in the popular state-managed college savings funds known as 529s dipped more than 10 percent in the third quarter of 2011. Estimated outflows were $354 million between July and September contrasted with inflows of $927 million in the same period of 2010, according to Financial Research Corp.

Indicative of the trend, contributions to the 529 plans managed by investment management firm Vanguard dropped 1.0 percent in 2011 after climbing 17 percent from 2009 to 2010. Parents of younger children are continuing to save, according to Vanguard, "but they may be concerned about the economy and market conditions and have cut back a little."

At the same time, college students are borrowing twice as much as they did a decade ago when adjusted for inflation, according to the College Board, and Americans now owe more on student loans than on credit cards.

Household borrowing on cards, car loans, student loans and other installment debt jumped almost 10 percent from October to November, according to the Federal Reserve, its biggest jump in a decade.

Welcomed by some as a sign of confidence in the economic recovery, others worried it was really a reflection of desperation.

"Apparent stronger consumption at year-end was associated with falling savings rates, compensating for stagnating income growth," Dennis Lockhart, president of the Federal Reserve Bank of Atlanta said on Jan. 11.

"I question whether this consumer spending momentum will be sustained without a pickup in income growth."

In a sign of concern among policymakers about the weak finances of many Americans, the Federal Reserve this month suggested an array of ways the U.S. government could help shore up the housing market.

House prices have fallen 33 percent from their 2006 peak, resulting in an estimated $7 trillion in household wealth losses and about 12 million homeowners are saddled with mortgages worth more than their properties.

Americans are steadily working off their overall debt levels, including their mortgages. Credit card balances, while little changed compared to a year ago, are down 18 percent from a peak in September 2008.

"It's not like it was a year or two ago when it really felt like a recession, and there was no job growth," said Scott Hoyt, a senior director of consumer economics at Moody's Analytics. "It's better than that and you can see that in the spending. But there's still no reason to go back to the free-spending