condition mean min max ZT0-3 11.0658 11.0658 11.0658 ZT4-7 10.5451 10.5451 10.5451 ZT8-11 15.3429 15.3429 15.3429 ZT12-15 22.26045 22.26045 22.26045 ZT16-19 14.952300000000001 14.952300000000001 14.952300000000001 ZT20-23 14.26295 14.26295 14.26295