condition mean min max ZT0-3 7.0147683333333335 5.664925 7.743245 ZT4-7 6.05127 6.05127 6.05127 ZT8-11 1.1049339999999999 1.1049339999999999 1.1049339999999999 ZT12-15 6.1733 5.217280000000001 7.12932 ZT16-19 8.52413 8.52413 8.52413 ZT20-23 6.219984999999999 6.219984999999999 6.219984999999999