condition mean min max ZT0-3 31.770632 31.770632 31.770632 ZT4-7 33.542098 33.542098 33.542098 ZT8-11 32.9550755 32.9550755 32.9550755 ZT12-15 35.114658500000004 35.114658500000004 35.114658500000004 ZT16-19 40.0368495 40.0368495 40.0368495 ZT20-23 34.1991725 34.1991725 34.1991725