condition mean min max ZT0-3 24.25336666666667 12.68555 30.65025 ZT4-7 8.601815 8.601815 8.601815 ZT8-11 16.21465 16.21465 16.21465 ZT12-15 31.628225 25.20115 38.0553 ZT16-19 33.73695 33.73695 33.73695 ZT20-23 43.49135 43.49135 43.49135