(FORTUNE Magazine) – America, the nation of immigrants, is shouldering a heavy price for its hospitality. The issue of the costs of immigration has come to a head in California this month, where a controversial proposal to limit social benefits to illegal aliens, called Proposition 187, went to a vote. But what about the legals? A new report by George Borjas, an economist at the University of California at San Diego and economic adviser to California Governor and Prop. 187 supporter Pete Wilson, shows that according to the last three censuses, legal immigrants have become disproportionately reliant on welfare compared with native-born residents. (Borjas says he has nothing to do with Prop. 187.) In 1970 about 6% of both immigrant and nth-generation American families received public assistance, excluding food stamps and health care. By 1990 the percentage increased to more than 9% for immigrants and to 7.4% for natives. The problem is that during the past two decades, each new wave of immigrants has been more welfare-prone than the last. In 1970, 5.5% of the newcomers who had been in the country less than five years received welfare. By 1990, 8.3% of the freshest arrivals were on the dole. Borjas attributes this trend to the accelerated influx of refugees, who have a much higher rate of welfare reliance than other immigrants. "Refugees have immediate access to a wide array of social services and programs that neither other legal immigrants nor natives qualify for," he says. Thus, almost half of all Cambodian and Laotian immigrants, many of whom are refugees, receive welfare, while less than 5% of Nigerians and Indians do.--J.A.

CHART: NOT AVAILABLE CREDIT: FORTUNE CHART/SOURCES: GEORGE BORJAS; CENSUS BUREAU CAPTION: Households receiving public assistance