The United States economy shrank for the first time in nine years during 1991, the Commerce Department said yesterday, and last year's closing quarter was even weaker than estimated a month ago.

In the final three months of 1991, national output expanded at only a 0.4 percent annual rate instead of 0.8 percent, the department said in a second and final revision of its growth estimates for the quarter. As a result, for all of 1991, total production of goods and services contracted by 0.7 percent - the first decrease in annual output in nine years since a 2.2 percent fall during the recession year 1982.

The department said the main factors in revising down its fourth-quarter estimate for gross domestic product were weaker exports than previously estimated as well as a smaller economic contribution from restocking of inventories.

The GDP is expected to grow at a more vigorous pace this year, with many economists forecasting annual rates of growth of 2 to 3 percent in the first half.

We want to hear, did we miss an angle we should have covered? Should we come back to this topic? Or just give us a rating for this story. We want to hear from you.