condition mean min max ZT0-3 1.6251760000000002 1.146922 2.1034300000000004 ZT4-7 2.31751 2.31751 2.31751 ZT8-11 2.1123849999999997 2.1123849999999997 2.1123849999999997 ZT12-15 0 0 0 ZT16-19 1.7821799999999999 1.7821799999999999 1.7821799999999999 ZT20-23 1.793365 1.793365 1.793365