condition mean min max ZT0-3 435.377612 435.377612 435.377612 ZT4-7 298.706502 298.706502 298.706502 ZT8-11 288.507172 288.507172 288.507172 ZT12-15 283.39770999999996 283.39770999999996 283.39770999999996 ZT16-19 370.35976949999997 370.35976949999997 370.35976949999997 ZT20-23 394.1317755 394.1317755 394.1317755