In Punjab state, the sex ratio at birth improved from 129 male births per 100 female births in 1999-2001 to 119 in 2005-07.

ECONOMIST: Letters

Previous studies reported that California recorded a 2% decrease in male births in December 2001 but the rate of female births didn't change.

WSJ: Exercise in Short Bursts Is Effective

They could also examine the effect of first-born children versus later births, sons versus daughters, and the impact on male versus female employees.

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