condition mean min max ZT0-3 1.204745 1.204745 1.204745 ZT4-7 1.86944 1.86944 1.86944 ZT8-11 1.4525199999999998 1.4525199999999998 1.4525199999999998 ZT12-15 0.678292 0.678292 0.678292 ZT16-19 0.6591835 0.6591835 0.6591835 ZT20-23 0.722737 0.722737 0.722737