condition mean min max ZT0-3 36.413875000000004 33.65975 39.168 ZT4-7 8.42731 8.42731 8.42731 ZT8-11 3.70281 3.70281 3.70281 ZT12-15 0 0 0 ZT16-19 14.792444999999999 14.792444999999999 14.792444999999999 ZT20-23 22.143 22.143 22.143