Those under age 18 (40%) and those 65 or older (10.7%) make up more than half of the 32.5 million Americans living in poverty, the Census Bureau said in a report entitled “Poverty in the United States: 1987.” About 20.6% of the 63.2 million Americans under 18 were living in poverty, compared to 12.2% of the elderly and 13.5% of all Americans, it said. The child poverty rate has been higher than those for other age groups since 1975; the increase in single-parent households and problems in collecting child support are blamed by anti-poverty groups. Earlier, the bureau had reported that nearly one-third of blacks lived in poverty. The poverty level varies with the size of the family unit. In 1987, it was $11,611 for a non-farm family of four.