"Women’s share of intended computer-science majors fell from a 44% peak in 1980 to 12% by the mid-2000s, rebounding only to 15% by 2011 in Sax et al.’s data."
The long-run trend gives the manuscript's ratchet image a concrete basis - women's share dropped sharply after the early-1980s peak and remained far below it through 2011.
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