condition mean min max ZT0-3 20.9634 20.9634 20.9634 ZT4-7 19.5405 19.5405 19.5405 ZT8-11 19.918100000000003 19.918100000000003 19.918100000000003 ZT12-15 18.5867 18.5867 18.5867 ZT16-19 26.824800000000003 26.824800000000003 26.824800000000003 ZT20-23 19.4334 19.4334 19.4334