Blacks have made progress in America over the past 20 years and are approaching the national norm in many areas, but "a major move . . . into mainstream middle-class America is not imminent," according to a study by Howard University sociologist John Reid published yesterday by the Population Reference Bureau.

"To be sure, a middle class is emerging, but it remains a minority of the black population and is far less affluent than the white middle class," Reid concluded.

By a wide margin, blacks still have less income, worse jobs, more poverty and more unemployment than whites, he said. Reid gave these measures of black America:

* Black population in the 1980 census was 26.5 million, or 11.7 percent of the national total, the highest proportion in recent times. The average age of American blacks in 1980 was 24.9 years, compared with 31.3 for whites.

* In 1910, 90 percent of blacks lived in the South, by 1940 the figure had dropped to 77 percent and today it is 53 percent.

In the past few years, blacks as well as whites have begun migrating back to the South to seek economic opportunity in a region that was growing faster than the older northern areas.

* As late as 1940 49 percent of blacks lived in urban areas, compared with nearly three-fifths of all whites. But by 1980, 85 percent of all blacks were in urban areas.

In 1960, Washington, D.C., was the only large city with a black majority (54 percent). By 1980, there were nine: Gary, Ind. (71 percent), Washington (70 percent), Atlanta (67 percent), Detroit (63 percent), Newark (58 percent), Birmingham (56 percent), New Orleans (55 percent), Baltimore (55 percent) and Richmond (51 percent).

* Blacks are still having more babies than whites: the average black woman has 2.3 children during her child-bearing years; the average white has 1.8.

* The proportion of out-of-wedlock births has been increasing among blacks and has now reached 55 percent, compared with 9 percent for whites.

* Life expectancy among blacks in 1979 was 68.3 years, more than double the figure at the start of the century, but still six years less than the 74.4 figure for whites. However, it was the smallest gap ever.

Infant mortality of black children was 21.8 per thousand live births, half of the 1960 figure but still twice the 11.4 figure for whites.

* About half of all black families with children were headed by single parents, compared with one-fifth for whites.

* In education, there has been substantial progress. School enrollment rates in 1980 "were virtually the same for blacks and whites."

Moreover, the percentage of blacks aged 18 to 24 in college nearly doubled from 10.3 percent in 1965 to 19.4 percent in 1981, compared with 26 percent for whites.

The proportion of blacks with a high school or a college education rose by a factor of 6 from 1940 to 1980:

Fifty-one percent of blacks had a high school degree in 1980 and 8 percent had a college degree. But the figures for whites still were higher, 71 percent (high school) and 18 percent (college).

* Despite these gains, black unemployment rates are still double those of whites.

At the end of the 1950s more than 10 percent of black job-seekers were unemployed, compared with under 5 percent for whites. In October, 1982, the figure for blacks was 20.2 percent, for whites 9.3 percent.

* Median family income of blacks continued to trail far behind that of whites: 57 percent in 1960, it rose to 62 percent in 1975 but in 1981 dropped back to 56 percent.

The poverty rate, which was 48 percent for black families in 1959 dropped to 30.8 percent by 1981, a substantial overall reduction, but still triple the 8.8 percent for white families.