(a) Males significantly different from females at ages 6, 7, 8 (p<0.02, Mann-Whitney test). (b) Males significantly different from females at ages 5, 6, 7, 8 (p≤0.001, Mann-Whitney test). (c) Males and females statistically similar (Mann-Whitney test). (d) Males significantly different from females at ages 6, 7, 8 (p≤ 0.01, Mann-Whitney test). (e) Males and females statistically similar (Mann-Whitney test). (f) Males significantly different from females at ages 3, 5, 6, 7, 8 (p<0.001) and at age 4 (p=0.03, Mann-Whitney test).