WASHINGTON, June 9 -- The fund that keeps tens of millions of older Americans out of poverty is now set to run empty a year sooner than the government said only twelve months ago. In their annual report on Tuesday, the trustees of Social Security projected that the retirement trust fund will be depleted in late 2032, pulling forward a reckoning that had been forecast for 2033 and turning an abstract long-term worry into something close enough to plan a career around.

The new date is three months earlier than the trustees said last June and a full year earlier than the report before that. Once the fund runs dry, the program would be able to pay only about 78 percent of scheduled retirement benefits out of incoming payroll taxes, an across...