A report in 2014 by the Bureau of Labor Statistics stated that employed men worked 52 minutes more than employed women on the days they worked, and that this difference partly reflects women's greater likelihood of working part-time. In the book "Biology at Work: Rethinking Sexual Equality", Browne writes: "Because of the sex differences in hours worked, the hourly earnings gap [...] is a better indicator of the sexual disparity in earnings than the annual figure. Even the hourly earnings ratio does not completely capture the effects of sex differences in hours, however, because employees who work more hours also tend to earn more per hour."