condition mean min max ZT0-3 21.272157 21.272157 21.272157 ZT4-7 43.444777 43.444777 43.444777 ZT8-11 57.995486 57.995486 57.995486 ZT12-15 35.617143 35.617143 35.617143 ZT16-19 36.1210065 36.1210065 36.1210065 ZT20-23 24.578347 24.578347 24.578347