condition mean min max ZT0-3 15.432501782500001 12.534534540000001 18.330469025 ZT4-7 9.8939136475 9.455820201 10.332007094 ZT8-11 8.634483978999999 8.585194598666666 8.683773359333333 ZT12-15 9.073601565 8.639701590333335 9.507501539666666 ZT16-19 10.835214867333335 9.757476474666667 11.91295326 ZT20-23 14.332322268333334 13.18414815 15.480496386666667