condition mean min max ZT0-3 9.023697 9.023697 9.023697 ZT4-7 11.76381 11.76381 11.76381 ZT8-11 9.990480999999999 9.990480999999999 9.990480999999999 ZT12-15 10.794406500000001 10.794406500000001 10.794406500000001 ZT16-19 12.214344 12.214344 12.214344 ZT20-23 11.2726625 11.2726625 11.2726625