Retirement angst has pervaded public discourse, as perennial fears about the future of Social Security are joined by attacks on Medicare and hand-wringing over the woeful financial condition of state and municipal pensions.

Corporate pensions that provide regular income for life receive less attention, but some of them also have significant long-term shortfalls and will absorb large amounts of companies' cash for years.

In the Standard & Poor's 500-stock index there are 334 companies that have defined-benefit pension obligations. In aggregate, those companies had 84 percent of what they needed to meet their obligations at the end of last year, according to a report Thursday by S&P Indices.

That was only a slight improvement over 2009, when companies had 82 percent of what they needed, despite solid market returns.

In the Philadelphia region, 49 publicly traded companies have pension obligations on their books, according to an Inquirer analysis of Securities and Exchange Commission filings. Those companies had 75 percent of the money needed to meet pension obligations at the end of their most recent fiscal years.

Howard Silverblatt, a senior index analyst at S&P Indices, said corporate pensions are in great shape compared with municipal and state funds, though different accounting rules make comparisons difficult.

For public companies, "it's a manageable expense," Silverblatt said, though not a small one, with pension contributions of $68.4 billion by S&P 500 companies last year and expected contributions of $41.1 billion this year. The seemingly large difference year-to-year is the product of a volatile mix of interest rates, returns on investments, and other factors.

"It's no longer the killer it was several years ago," he said.

From the perspective of the corporations that administer pension plans, it has already helped that about half of the nation's private defined-benefit pension plans are either frozen, which means that current participants earn no additional benefits, or the plans are closed to new hires.

Historically, defined-benefit pensions have been a significant source of income only for people 65 and older who are in the top 40 percent of earners during retirement, according to data from the Employee Benefits Research Institute in Washington.

The bottom 40 percent have consistently derived 80 percent to 90 percent of retirement income from Social Security. Those in the middle have had a more even mix, though they still get three-fourths of their retirement income from Social Security.

Despite the shift away from defined-benefit pensions, which put the financial risk on employers, to a retirement-savings system that puts the risk on the individual, some companies still face a significant funding burden.

Cigna Corp., for example, a Center City medical insurer that froze its plans in 2009, had a $1.5 billion pension shortfall Dec. 31. The company's funding ratio of 67.4 percent ranked as the fourth worst in a report on the nation's 100 largest corporate pension funds by Milliman, a pension-advisory firm.

A Cigna spokeswoman said the company has always made legally required contributions and intended to contribute at least $250 million before-tax per year. "We are committed to fully funding the pension plan, and under normal market conditions, expect the pension plan to be fully funded within the next four to five years," Gloria Barone said.

Experts cautioned that the financial picture painted by annual reports to the SEC is not the one companies use when deciding whether to pay into pension funds. Those decisions are made using a significantly different set of rules defined by the Pension Protection Act of 2006.

The SEC disclosures are useful for looking at broad trends in funding, but "it's a little challenging to compare companies because there's more noise in the numbers," said David Suchsland, head of Towers Watson's Philadelphia retirement practice.

Some companies, such as TE Connectivity Ltd., formerly Tyco Electronics Ltd., in Berwyn, have a significant overseas presence with pension obligations in countries that do not require assets to be set aside for pensions. TE's U.S. funds were 83 percent funded on Dec. 31. Its non-U.S. funds were just 50 percent funded.

Like TE, Carpenter Technology Corp., a Wyomissing, Pa., stainless-steel producer, has active pension plans.

Despite a significant 34 percent gap in pension funding reported in its annual report for the year ended June 30, 2010, the fund is solidly financed under Pension Act rules. In April, Carpenter made its first contribution - $3.8 million - to the fund since 1986, said Thomas F. Cramsey, vice president and chief accounting officer.

Cramsey said Carpenter had no plans to freeze its pension plan for its workers.

"Just the fact that we were in such well-funded status for so long, there's no reason to change that. We have very long-tenured employees at Carpenter," making the pension an extremely valuable benefit, he said.

Contact staff writer Harold Brubaker at 215-854-4651 or hbrubaker@phillynews.com.