condition mean min max ZT0-3 5.335934999999999 5.335934999999999 5.335934999999999 ZT4-7 3.37777 3.37777 3.37777 ZT8-11 5.999784999999999 5.999784999999999 5.999784999999999 ZT12-15 8.56227 8.56227 8.56227 ZT16-19 6.270315 6.270315 6.270315 ZT20-23 6.66519 6.66519 6.66519