Final census figures released by the District government yesterday appear to confirm that whites are moving into parts of the city, such as Capitol Hill and Adams-Morgan, that are experiencing so-called "gentrification.

The 1980 data show that while the number of blacks and whites is down in the city, two of the city's eight voting wards have undergone noticeable increases in the percentage of white population since the 1970 census.

In Ward 6, for example, which includes the Capitol Hill area, whites now make up 20 percent of the population compared with 15 percent a decade ago.

The number of whites in the ward also increased, from 13,800 to 15,100, the census figures show, while the number of blacks and whites declined in varying degrees in all other wards.

In Ward 1, which includes Adams-Morgan, the percentage of white residents increased from 20 percent to 23 percent, although the actual number of whites in the area declined. The other wards all showed a slight decrease in the percentage of white residents, averaging one or two percentage points.

The ward with the largest concentration of blacks continues to be Ward 7, encompassing the far eastern corner of the city. The city ward with the greatest concentration of whites continues to be Ward 3, the affluent section of town west of Rock Creek Park.

Blacks make up 95 percent of the population in Ward 7, the figures show, compared with about 96 percent in 1970. Across town, whites make up 92 percent of the population in Ward 3, compared with 95 percent 10 years ago.

The census shows that for the city as a whole the ratio of blacks to whites was essentially the same in 1980 -- about 70 percent to 27 percent -- as in 1970. But it also showed that during the last half of the decade blacks stepped up their flight from the city, while the departure of whites slowed significantly.

Overall, the city's population declined from 756,510 to 637,651, a l5.7 percent decrease.