Age group
≤ 30 31 to 40 ≥ 41
Median 40ab 36.5a 36b
Percentile 25 35 30 30
50 40 36.5 36
75 45 40 40

Working hours per week based on the non-parametric Kruskal-Wallis test
aThe significance level is 0.05; basymptotic significance is displayed.
Based on non-parametric Kruskal-Wallis test × 2 = 15.753, lls = 2, P = 0.001, abP < 0.01.