condition mean min max ZT0-3 19.427999999999997 16.62315 21.8587 ZT4-7 10.132314999999998 10.132314999999998 10.132314999999998 ZT8-11 6.569305 6.569305 6.569305 ZT12-15 8.917584999999999 6.96707 10.8681 ZT16-19 11.323285 11.323285 11.323285 ZT20-23 16.62155 16.62155 16.62155