condition mean min max ZT0-3 188.509061 188.509061 188.509061 ZT4-7 139.299432 139.299432 139.299432 ZT8-11 141.96507300000002 141.96507300000002 141.96507300000002 ZT12-15 164.5405005 164.5405005 164.5405005 ZT16-19 158.60735 158.60735 158.60735 ZT20-23 147.92503349999998 147.92503349999998 147.92503349999998