condition mean min max ZT0-3 8.493295 8.493295 8.493295 ZT4-7 30.3189 30.3189 30.3189 ZT8-11 34.493849999999995 34.493849999999995 34.493849999999995 ZT12-15 22.0831 22.0831 22.0831 ZT16-19 5.97995 5.97995 5.97995 ZT20-23 4.290405 4.290405 4.290405