condition mean min max ZT0-3 1.7884200000000001 1.030915 2.446695 ZT4-7 1.0638100000000001 1.0638100000000001 1.0638100000000001 ZT8-11 1.016329 1.016329 1.016329 ZT12-15 1.6490725 1.424215 1.87393 ZT16-19 1.6593849999999999 1.6593849999999999 1.6593849999999999 ZT20-23 3.845015 3.845015 3.845015