The great defence against stagnating male wages in America over the last few decades has been the two-worker family. The latest data show that the median income of two-worker families was nearly $71,000. If only the husband worked, the median family income was $41,000.

Small wonder the proportion of two-worker families has soared in America, to 62 per cent of all married couples from 39 per cent in 1970.

But valuable new research by two economists, Stephen J. Rose and Heidi Hartmann, shows that such measures substantially overstate what women earn over time. A big reason is that women work far fewer hours than men on average and often drop out of the work force for years at a time. So Rose and Hartmann decided to study actual earnings histories of men and women over 15 years. The researchers compared the earnings of men and women from 1983 to 1998 in the prime work years between ages 26 and 59. They found that women on average earned only 38 per cent of what men did. Adding it up, they found that the average woman earned $273,592 over 15 years, compared with $722,693 for men.

But hours alone do not account for the discrepancy in pay over time. The analysis turns up continuing evidence of gender segregation. A far higher proportion of females have jobs that pay at the bottom of the income scale, and fewer of them climb to jobs of higher quality. Hartmann and Rose argue, most disturbingly, that these tendencies are self-reinforcing. Because wives usually earn less, they are more likely to give up their jobs to take care of children.

?NYTNS