Rendall and Rendall (2016) found that women prefer occupations where their skills depreciate slowest when taking time out from motherhood. Verbal and reading skills depreciate at a far slower rate than mathematical and scientific skills so this gives women yet another strong reason to avoid science, technology, engineering and maths (STEM) careers.
we show that college educated women avoid occupations requiring significant math skills due to the costly skill atrophy experienced during a career break. In contrast, verbal skills are very robust to career interruptions.
The results support the broadly observed female preference for occupations primarily requiring verbal skills – even though these occupations exhibit lower average wages. Thus, skill-specific atrophy during employment leave and the speed of skill repair upon returning to the labour market are shown to be important factors underpinning women’s occupational outcomes.
Not only do women have vastly superior verbal and reading skills, worth somewhere near 6 to 12 months extra schooling, these skills do not depreciate much during career breaks. Indeed, reading and verbal skills tend to naturally increase with age until your late 60s.
Maths skills get rusty if not used while knowledge of computer languages and the like and of specific technologies can be quickly overtaken by events while on maternity leave. Rendall and Rendall (2016) again
… college educated females avoid math-heavy occupations, and pursue verbal-heavy occupations instead. This is due to the high skill atrophy associated with math skills, and the ability of verbal skills to act as “skill insurance” against gaps.
Additionally, for college educated individuals, math is the skill most vulnerable to loss during employment gaps, which also implies a slow rebuilding post-break. In contrast, non-college educated individuals experience a much smaller math skill loss.
Rendall and Rendall’s point about college educated women avoiding maths heavy occupations even if it costs them wages so as to maximise the lifetime income may explain the larger gender wage gap at the top of the income distribution than at the bottom.
At the bottom of the income distribution, skill atrophy do not really matter much. At the top, it do. Women make occupational choices where annual income may be lower but lifetime income may be higher because of the lower rates of skill depreciation when they are out having children.