The federal government has shelled out more than $700 million in paid leave to more than 57,000 employees who were home from work for time periods stretching from one month to three years, a Government Accountability Office report has found.

In a 62-page report published Monday, the GAO analyzed why so many federal employees were home and getting paid for such long periods of time and they discovered a variety of reasons.

In many cases, employees were home awaiting the outcome of investigations into alleged misconduct and criminal actions. Some racked up paid leave for “physical fitness activities,” and others were away from work seeking professional development. Employees also took paid leave for “recuperation” from overseas work.

Hundreds of federal employees remained at home, collecting a paycheck, for years.

The report found that during a three-year period beginning in 2011, 263 employees remained on paid leave for one to three years at a cost of $31 million.

In some cases, about five percent of the time, the federal government couldn’t come up with a reason why some employees were home on paid leave.

Overall, paid leave for federal government workers, excluding holidays, cost billions of dollars from 2011 to 2013, the GAO report found, but comprised less than one percent of all federal government salaries paid during that time period.

The vast majority of the 1.2 million federal employees analyzed in the report — about 97 percent — took fewer than 20 paid leave days, excluding holidays. More than 940,000 employees took two to five paid leave days outside of holiday breaks, the report found.

Nearly $600 million was paid to employees who took two to four weeks of paid leave, but these employees were not considered among the group with “higher than average charges,” which the GAO defined as 51 days or longer of paid leave.

Sen Chuck Grassley, R-Iowa, said he asked for the GAO probe after his own investigators uncovered unusual instances of paid leave. In one case, Grassley said, Inspector General of the National Archives and Records Administration, Paul Brachfeld, was put on paid leave "against his will for nearly two years" before retiring.

“These employees should be working for the taxpayers, not getting paid to stay home,” Grassley said in a statement Monday. “Paid leave is an excuse for managers not to manage and put off a decision on what to do with employees accused of misconduct or who blow the whistle or dispute a personnel action. The mentality seems to be out of sight, out of mind, and that’s not the way to run the government or act responsibly with tax dollars.”

In some cases, administrative errors played a role in high paid leave totals. The Department of Interior, for example, recorded some employee vacation time as paid administrative leave.

The GAO report found recording of administrative leave “inaccurate and inconsistent” across federal agencies and included recommendations aimed at improving the consistency and accuracy of collecting payroll information.