condition mean min max ZT0-3 7.81849 7.57024 8.06674 ZT4-7 19.944850000000002 19.944850000000002 19.944850000000002 ZT8-11 21.4049 21.4049 21.4049 ZT12-15 0 0 0 ZT16-19 12.2363 12.2363 12.2363 ZT20-23 7.839805 7.839805 7.839805