condition mean min max ZT0-3 134.471224 134.471224 134.471224 ZT4-7 173.95684799999998 173.95684799999998 173.95684799999998 ZT8-11 181.559474 181.559474 181.559474 ZT12-15 174.7313245 174.7313245 174.7313245 ZT16-19 97.282498 97.282498 97.282498 ZT20-23 67.605995 67.605995 67.605995