WASHINGTON - The Obama administration set a record again for censoring government files or outright denying access to them last year under the Freedom of Information Act, according to a new analysis of federal data by the Associated Press.

The government took longer to turn over files when it provided any, said more regularly that it could not find documents, and refused a record number of times to turn over files quickly that might be especially newsworthy.

It also acknowledged in nearly 1 in 3 cases that its initial decisions to withhold or censor records were improper under the law - but only when it was challenged.

Its backlog of unanswered requests at year's end grew remarkably by 55 percent to more than 200,000. It also cut by 375, or about 9 percent, the number of full-time employees across government paid to look for records. That was the fewest number of employees working on the issue in five years.

The government's new figures, published Tuesday, covered all requests to 100 federal agencies during fiscal 2014 under the Freedom of Information law, which is heralded globally as a model for transparent government.

Citizens, journalists, businesses, and others made a record 714,231 requests for information. The United States spent a record $434 million trying to keep up. It also spent about $28 million on lawyers' fees to keep records secret.

"This disappointing track record is hardly the mark of an administration that was supposed to be the most transparent in history," said Sen. John Cornyn (R., Texas).

The new figures showed the government responded to 647,142 requests, a 4 percent decrease over the previous year. It more than ever censored materials it turned over or fully denied access to them, in 250,581 cases. Sometimes, the government censored only a few words or a phone number, but other times it completely marked out nearly every paragraph on pages.

The White House touted its success under its own analysis. It routinely excludes from its assessment cases when it could not find records, a person refused to pay for copies, or the request was determined to be improper under the law, and said under this calculation it released all or parts of records in 91 percent of requests - still, using the White House's own math, a record low since President Obama took office.

"We actually do have a lot to brag about," White House spokesman Josh Earnest said.

Under the president's instructions, the U.S. should not withhold or censor files merely because they might be embarrassing, but federal workers last year were found to misapply the law. In e-mails AP obtained from the National Archives and Records Administration about who pays for Michelle Obama's expensive dresses, the agency blacked-out a sentence under part of the law intended to shield personal, private information, such as Social Security numbers or home addresses. But it failed to censor the same passage on a subsequent page.

The sentence: "We live in constant fear of upsetting the WH [White House]."