condition mean min max ZT0-3 1.427395 1.337355 1.5174349999999999 ZT4-7 0.8456589999999999 0.8456589999999999 0.8456589999999999 ZT8-11 1.34713 1.34713 1.34713 ZT12-15 0 0 0 ZT16-19 1.5585399999999998 1.5585399999999998 1.5585399999999998 ZT20-23 1.355505 1.355505 1.355505