Each year, the U.S. Education Department distributes billions of dollars in grants to schools, districts, states and nonprofits, and the agency needs to do a better job making sure that it is adequately monitoring whether the money is achieving its intended goals, according to a Government Accountability Office report.

Many grants are doled out over multiple years, and grantees are supposed to show “substantial progress” toward their goals  to receive their next installment of funds. The GAO found that in 2015, during the Obama administration, department employees did not consistently adhere to protocols for documenting their efforts to monitor grants, making it impossible for outside investigators to determine whether grantees made enough progress to get the money they received.

The GAO studied 75 grants worth $272 million that Education awarded in fiscal  2015, a small sample of the $4 billion in grants distributed to thousands of recipients that year. In 69 of those 75 cases, official Education grant files were missing documentation of performance. For instance, grantees’ progress should have been documented in 179 separate reports, but GAO investigators could find only 121 such reports in the official files.

In a March letter appended to the GAO report, Education Department officials said that all of the performance reports had been completed, though some were not stored in official grant files. They agreed with a GAO recommendation to establish new written procedures describing how supervisors should ensure that employees are appropriately monitoring grantees, but emphasized that no federal funds were improperly distributed.

Sen. Lamar Alexander (R-Tenn.), who requested the GAO investigation, said he hopes that Secretary Betsy DeVos makes “serious improvements” to correct the deficiencies.

“When taxpayers spent $4 billion on competitive grants administered by the Obama administration’s Education Department in 2015, they expected proper oversight — to ensure the money was spent as intended and the results were measured,” Alexander said in a statement. “Today’s report shows us the department didn’t deliver.”

Education Department spokeswoman Liz Hill also noted that the GAO identified problems that occurred during the previous administration. “Secretary DeVos finds this report appalling and unacceptable and is committed to ensuring the U.S. Department of Education delivers on its commitment to serving students while prudently safeguarding taxpayer dollars,” Hill said.