condition mean min max ZT0-3 20.851149999999997 20.851149999999997 20.851149999999997 ZT4-7 11.17115 11.17115 11.17115 ZT8-11 13.175049999999999 13.175049999999999 13.175049999999999 ZT12-15 12.0075 12.0075 12.0075 ZT16-19 16.874850000000002 16.874850000000002 16.874850000000002 ZT20-23 19.75175 19.75175 19.75175