Anyone have any ideas how to do this question?

There has been a decline in women's participation during the 1990s despite popular notions of IT being gender neutral in the 1980s. This same 1990's decline is evident in the US university data but is not evidencent in many European and Asian countries where the number of women equal the numbers of men'.


Any websites related to why less women participate in IT are welcome.
I need for reference.
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