condition mean min max ZT0-3 26.449416666666668 14.99005 35.7909 ZT4-7 11.5489 11.5489 11.5489 ZT8-11 13.718350000000001 13.718350000000001 13.718350000000001 ZT12-15 40.731725000000004 36.810900000000004 44.652550000000005 ZT16-19 37.22580000000001 37.22580000000001 37.22580000000001 ZT20-23 43.6387 43.6387 43.6387