condition mean min max ZT0-3 30.69485 30.69485 30.69485 ZT4-7 41.3954 41.3954 41.3954 ZT8-11 25.45195 25.45195 25.45195 ZT12-15 24.97285 24.97285 24.97285 ZT16-19 38.559749999999994 38.559749999999994 38.559749999999994 ZT20-23 43.31165 43.31165 43.31165