condition mean min max ZT0-3 4.15501367375 3.575101665 4.7349256825 ZT4-7 3.379011131 2.885181696 3.872840566 ZT8-11 5.527533667749999 4.7091239185 6.345943417 ZT12-15 7.246252437500001 6.8429747195 7.649530155500001 ZT16-19 7.5983672572500005 7.513057954500001 7.68367656 ZT20-23 8.6376098705 8.5582999365 8.7169198045