condition mean min max ZT0-3 6.2245075 5.247895 7.2011199999999995 ZT4-7 5.936835 5.936835 5.936835 ZT8-11 6.7715499999999995 6.7715499999999995 6.7715499999999995 ZT12-15 0 0 0 ZT16-19 9.03218 9.03218 9.03218 ZT20-23 9.89039 9.89039 9.89039