Some say there are more women in the workforce because the economy is worse, and therefore, homes require two incomes.
But the situation is said to be the opposite – more women entered the workforce due to both being better educated (more women graduate from college than men, since the early 1980s) and the monetary return of working is higher than staying at home (e.g. doing home labor to save money).
Most Married Women with Children Were Working By the Late 1970s – Economist Writing Every Day
Another way to view this
“Zero income” generally refers to retirees, the disabled who cannot work, and some others.
Different surveys show somewhat different percentages, depending on how they defined each category.
