WASHINGTON — The U.S. economy grew at a meager 1 percent annual pace this spring, slower than previously estimated. The downward revision stoked fears that the economy is at risk of another recession.

Fewer exports and weaker growth in business stockpiles led the government to lower its growth estimate for the April-June quarter from the initial 1.3 percent rate.

The economy expanded only 0.7 percent in the first six months of the year, the Commerce Department said Friday.

Nine of the past 11 recessions since World War II have been preceded by a period of growth of 1 percent or less, economists note.

Federal Reserve Chairman Ben Bernanke said the U.S. is on track for long-term economic growth, which helped the stock market turn positive after earlier losses.

Economists said the revision hasn’t changed their growth forecasts. Most expect slightly better growth in the second half of the year of roughly 1.5 percent to 2 percent.