WASHINGTON — Washington. -- "If we could first know where we are and whither we are tending, we could better judge what to do, and how to do it.'' I doubt that Abraham Lincoln had the census in mind when he uttered those words, but they certainly fit. Figures from the 1990 census have been gushing forth from government computers, and they tell us a lot about ourselves and how the colors and languages of America are changing.
As to where we are, for example, a whole lot more of us are living in the South and West. Of the 15 states on the mainland U.S.
that gained 10 percent or more in population between 1980 and 1990, 12 are either Southern or Western. Conversely, the states that grew more slowly or lost population tend overwhelmingly to be in the Northeast and Middle West.
Where we're headed is in the direction of an older population, with larger minority segments, changing jobs and changing families.
The ''traditional'' American family -- two parents with children -- continued to decline during the 1980s, albeit at a slower pace than in the 1970s. In 1970, 40 percent of the nation's households consisted of a married couple and one or more children under age 18. That proportion dropped to 31 percent in 1980 and to 26 percent in 1990. The number of single parents rose 41 percent between 1980 and 1990 to 9.7 million (8.4 million of them women, many heading households of poverty.)
But perhaps the most startling and significant figures to emerge from last year's census have to do with immigration. Some 8 million foreigners poured into the United States during the 1980s, 6 million legally, 2 million without documents. That is the largest 10-year immigration total since the first decade of the 20th century.
The Census Bureau has not tabulated the total number of foreign-born living in the U.S. now, but Jeffrey Passel of the Urban Institute estimates that the figure is approaching 20 million, an all-time high. That represents about 8 percent of the total population. In 1980, the United State had about 14 million foreign-born residents.
With nearly three-fourths of the immigrants of the '80s settling in just six states, they are a key factor in those states' growth. About 2.3 million of California's 3.2 million added population arrived from foreign countries, which means that the state would have gained only two or three new seats in Congress, instead of seven, without the immigrants.
New York, which was second with 950,000 new immigrants, and Illinois, fifth with 401,000, both would have lost population in the decade were it not for immigration. The other three states where most immigrants settled during the 1980s were Texas, Florida and New Jersey.
The source of immigration has shifted greatly in recent decades. Between 1981 and 1990, 44 percent of legal immigrants to the U.S. came from Asia and 40 percent from Latin America (led by Mexico with 13 percent). Only 14 percent, about one in seven, came from the traditional leading sources, Europe and Canada.
Some of the 1990 figures may yet change. The Census Bureau has acknowledged that as many as 6 million people, including 1.8 million Hispanics, may have been missed. Pressure continues for an adjustment in the count.
With or without an adjustment, we'll have millions of facts telling us ''where we are'' and ''whither we are tending.'' It will be up to us to use them wisely in deciding ''what to do and how to do it.''
Carl T. Rowan is a syndicated columnist.