condition mean min max ZT0-3 15.32245 15.32245 15.32245 ZT4-7 7.180075 7.180075 7.180075 ZT8-11 4.45864 4.45864 4.45864 ZT12-15 10.267635 10.267635 10.267635 ZT16-19 21.18645 21.18645 21.18645 ZT20-23 32.4314 32.4314 32.4314