For men with degrees, who want marriage and children (“marriage” includes long term relationships with a woman):

The men date and sometimes marry, women with degrees of a similar or slightly lower age, in the first 3-5 years after they leave University. However after this period, the single men remaining, tend to start dating women younger than them, many of whom do not have degrees and may marry them.

The remaining men who then get into their 30’s, often marry women 3-8 years younger than them, the majority of whom do not have degrees. This then means that Tradesmen often marry women who do not have degrees (as normal) and these women are skilled, semi-skilled or unskilled.

Unskilled men who want to get married are then left with fewer women to choose from. However this is not too much of a problem, as there are many more unskilled women that want marriage and a family than unskilled men who want the same.

Of course, men with degrees often opt out of marriage and children altogether. However these men are not included in the above trend.

The “casualty” of this trend are are mainly a lot of unmarried women with degrees who want marriage and children. However, this is not a problem to society as these women continue working (and occasionally opt to become single mothers).