condition mean min max ZT0-3 219.84662 219.84662 219.84662 ZT4-7 215.80284849999998 215.80284849999998 215.80284849999998 ZT8-11 278.7827885 278.7827885 278.7827885 ZT12-15 319.937101 319.937101 319.937101 ZT16-19 296.25005799999997 296.25005799999997 296.25005799999997 ZT20-23 300.56921850000003 300.56921850000003 300.56921850000003