Older Americans flexed their political muscles last November, while interest in choosing a new president flagged among other age groups, the Census Bureau reports.

Some 68.8 percent of people 65 and over reported going to the polls last fall, the only age group to show an increase from the election four years earlier, according to the analysis released on Tuesday. Senior citizens voted at a 67.7 percent rate in 1984."The elderly have been getting a lot of attention and have become a great deal more active then ever before," said Census Bureau statistician Jerry Jennings. "They are becoming a much more self-conscious group than before and are beginning to recognize their power."

While the over-65 group was tops in turnout, the 45-to-64 age segment wasn't far behind at 67.9 percent last November. But that was down from 69.8 percent four years earlier.

Turnout by voters aged 25 to 44 fell from 58.4 percent to 54.0 percent, and in the 18 to 24 group it dropped from 40.8 percent to 36.2 percent.

Overall, the census analysis found voter turnout down 3 percentage points from 1984 and - at 57 percent - the lowest since the bureau began asking about voting in 1964.

As usual, more people told the Census Bureau they had voted than there were votes actually cast, a phenomenon which the bureau gently terms "misreporting."

The drop in turnout was greatest for blacks and Hispanics, the Census study found.

Only 51.5 percent of voting-age blacks said they had cast ballots, down from 55.8 percent four years earlier. For Hispanics the decline was from 32.6 percent to 28.8 percent.

The white turnout fell from 61.4 percent to 59.2 percent between 1984 and 1988.

Women held their lead over males in voting, 58.3 percent to 56.4 percent last year. In 1984 women had led 60.8 percent to 59.0 percent.

Turnout in the West fell from 58.5 percent to 55.6 percent.

Sampling of turnout during '88 election

Here's a smpling of the percentage of voting-age Americans who reported casting a ballot in the election:

State Turnout

Utah 69.8

Texas 53.9

Arizona 54.0

California 51.7

Clorado 65.4

Idaho 63.9

Montana 68.6

Nevada 46.9

New Mexico 54.6

New York 54.0

Oregon 63.8

Wyoming 61.8