condition mean min max ZT0-3 19.705783333333333 13.0138 25.284 ZT4-7 11.770354999999999 11.770354999999999 11.770354999999999 ZT8-11 16.48505 16.48505 16.48505 ZT12-15 45.653949999999995 41.286699999999996 50.0212 ZT16-19 38.337599999999995 38.337599999999995 38.337599999999995 ZT20-23 38.80765 38.80765 38.80765