WASHINGTON - The economic crisis means wage earning mothers and stay-at-home dads are increasingly becoming the norm, new U.S. Census Bureau figures show.

The number of mothers who were the only working spouse rose for the third straight year, according to Census Bureau figures released Friday. The number of fathers who were the only working spouse dropped, and the number of stay-at-home dads ticked higher.

U-M Professor Pamela Smock

"The economic crisis is heavily affecting families, and what the latest data show is that gender roles are flexible and are going in the direction of egalitarian roles," said Pamela J. Smock, a sociology professor at the University of Michigan.

Massive job losses are behind the traditional gender role shift; the number of working mothers in the U.S. who are the sole breadwinners in their families rose last year to an all-time high, and the number of stay-at-home fathers edged higher.

The figures are for married couples with children under 18.

Smock said the shifts could have lasting effects after the economy rebounds, as people become more accustomed to the roles of wage earning mothers and stay-at-home fathers.

In most households with mothers as wage earners, both parents were working until the husband was laid off or retired, and the wife remained in her job. In other situations, a non-working wife may have rejoined the labor force, in a growing industry such as teaching or health care, to sustain the family income after the husband was let go.

By the numbers, about 4 percent or 963,000 moms were the only parent in the labor force. The share of fathers as the sole worker was much bigger — 28.2 percent or 7.3 million — but still the lowest since 2001. The share of couples who both work stayed the same at 66 percent or 17 million.

The recession's toll has been harder on male-dominated industries such as construction and manufacturing. There are also longer-term cultural changes at work, too, as more women earn college degrees and the better job opportunities they bring.

The latest trends coincide with overall increases in women in the work force. In fact, women are close to outnumbering men in the work force for the first time: Women held 49.9 percent of the 131 million U.S. jobs last November, the most recent data available.

Analysts cautioned the latest numbers may be somewhat illusory, since women still hold fewer executive positions and their jobs, particularly among mothers, are often part-time.

By Hope Yen, The Associated Press.