Women's participation in the labour market has considerably increased since the second half of the 20th century, closing in on men in many countries. However, they still spend more time than men on house-keeping work everywhere. Their now-massive participation in the job market has not seemed to help redefine gender roles in the family. Why do men and women make choices that conform so much to tradition? Can an economic calculation shed light on the situation? We attempt to answer these questions based on the 1998-1999 and 2010-2011 Time Use surveys, by analysing how tasks are shared in two-worker couples where the woman is heavily involved in the job market. To this end, we use professional investment indices that take either other women or their partners as a reference. We show that women tend to perform less house-keeping work when they are more involved in the job market. On the other hand, the time that their partner spends on household labour increases only slightly and insignificantly, unless their wife has a higher social status than them. In this case, they spend significantly more time on house-keeping work, which we do not observe if their partner only has a higher level of education or higher monthly wages than them. In particular, these results imply that even if the difference in time spent on household tasks within couples is less pronounced than the average in households where the woman is heavily involved in the job market, we do not observe a shift in roles that would imply an efficient distribution of tasks.