KABUL, Afghanistan — An American aid project in Afghanistan that was billed as the world’s biggest program ever designed purely for female empowerment has been a failure and a waste of taxpayers’ money, the head of a government watchdog agency has charged.

The project by the United States Agency for International Development, which was named Promote, was originally budgeted at $280 million and was supposed to help 75,000 Afghan women get jobs, promotions, apprenticeships and internships.

Three years later, one of the few concrete results cited in a study of the project released on Thursday by the Special Inspector General for Afghan Reconstruction was the promotion of 55 women to better jobs. But the report said it was unclear whether the program could even be credited for those promotions.

“We can’t find any good data that they’re helping any women,” said John L. Sopko, the head of the watchdog agency, which was established by Congress to monitor American spending in Afghanistan.