condition mean min max ZT0-3 1.1350033333333334 0.80572 1.3686500000000001 ZT4-7 0.811128 0.811128 0.811128 ZT8-11 1.02011 1.02011 1.02011 ZT12-15 1.719425 1.71479 1.72406 ZT16-19 1.67317 1.67317 1.67317 ZT20-23 1.9759600000000002 1.9759600000000002 1.9759600000000002