condition mean min max ZT0-3 41.081625 35.55215 46.6111 ZT4-7 15.022100000000002 15.022100000000002 15.022100000000002 ZT8-11 25.70245 25.70245 25.70245 ZT12-15 0 0 0 ZT16-19 19.64605 19.64605 19.64605 ZT20-23 27.95785 27.95785 27.95785