condition mean min max ZT0-3 19.57445 18.67625 20.516399999999997 ZT4-7 13.885200000000001 13.885200000000001 13.885200000000001 ZT8-11 17.50915 17.50915 17.50915 ZT12-15 25.95475 25.084400000000002 26.8251 ZT16-19 24.19595 24.19595 24.19595 ZT20-23 22.96045 22.96045 22.96045