condition mean min max ZT0-3 26.441257 26.441257 26.441257 ZT4-7 65.998343 65.998343 65.998343 ZT8-11 46.978838999999994 46.978838999999994 46.978838999999994 ZT12-15 25.325597000000002 25.325597000000002 25.325597000000002 ZT16-19 17.918352 17.918352 17.918352 ZT20-23 13.793290500000001 13.793290500000001 13.793290500000001