condition mean min max ZT0-3 72.87635 72.87635 72.87635 ZT4-7 83.01175 83.01175 83.01175 ZT8-11 8.666545 8.666545 8.666545 ZT12-15 7.55808 7.55808 7.55808 ZT16-19 22.58165 22.58165 22.58165 ZT20-23 66.7098 66.7098 66.7098