In 1989 sociologist Arlie Hochschild described what working wives already knew: after the paid day ended, employed women worked what added up to an extra month of twenty-four-hour days each year at home. The workplace had admitted women, but the household never renegotiated. Later time-diary research shrank that estimate, and the gap has narrowed, but it has never closed.
Hochschild's 'extra month' figure came from averaging older time-use studies, and later work found a smaller gap. Near-equal total workloads do not erase women's more fragmented work and mental load, which diaries capture poorly.