condition mean min max ZT0-3 16.525433333333332 12.65545 19.57865 ZT4-7 16.37605 16.37605 16.37605 ZT8-11 10.7711 10.7711 10.7711 ZT12-15 21.099024999999997 18.2912 23.90685 ZT16-19 16.55125 16.55125 16.55125 ZT20-23 21.1996 21.1996 21.1996