condition mean min max ZT0-3 8.411848333333333 4.536685 10.963175 ZT4-7 5.962755 5.962755 5.962755 ZT8-11 13.78135 13.78135 13.78135 ZT12-15 18.230800000000002 12.6131 23.8485 ZT16-19 16.0611 16.0611 16.0611 ZT20-23 16.9015 16.9015 16.9015