Ethnic variation of people not in labour force

Just before Xmas Stats NZ released a report about people not in the labour force. The graph that caught my eye is below:

At  a glance you could be forgiven for thinking that Europeans are spending a lot of time playing around while Maori, Pacific and Asian people spend a lot of time studying.

The explanation for the divergence is provided:

This difference for the European ethnic group can be attributed to its different age structure when compared with the other ethnic groups. The median age of the European people not in the labour force was 66 years in the September 2016 quarter. In contrast, the median age was 30 years for Pacific peoples, 32 years for Māori, and 33 years for the Asian ethnic group. If we restrict the population to only look at those aged under 65 years, then study or training is the most-common main activity, and looking after a child is the second most-common main activity for all four of the ethnic groups looked at.

The median age of European people not in the labour force is double - or more than double - that of the next three largest ethnic groups.

Astonishing variation, but when you think about it, not that surprising. The European dominance of the baby boomer ranks and older accounts for this large anomaly.