Women earn less than men do．For example, in 1998 the hourly wages of women in the U．S．were 26% less than those of men．The gap between male and female incomes becomes wider with age．The gap between the labor incomes of young women and young men varies．It's also clear that jobs in which women are concentrated pay less．The larger the number of workers who are women in an industry, the lower the average wages.
Why do women earn less than men do? Are the differences explained by the fact that women are looked down upon? If so, the government has to intervene (干预) ,to force the employers to pay equal wages to equal jobs．However, there is no agreement among economists about the causes of the gap．One view argues that women on the average have chosen low-paid jobs in which workers enjoy the of entering and leaving the labor force, which reduces their years of experience relative to men．Other people say the gap can also be explained by the difference in educational background.
Much of the gap, however, has not been fully explained．It might be the result of some prejudice (偏见) against women．It is this part that has produced calls for government action．What would happen if the government did intervene to increase the wages paid to women? One possibility is that incomes for women as a group might actually decline (下降)．An increase in wage decreases the quantity of labor imput demanded, resulting in decreased employment as the rate of hiring r~ew workers declines．The result will be a surplus (过剩) of labor．Those who can find jobs might be better off while those who had jobs might find themselves out of work.
The difference in labor incomes is most obvious between ______.