condition mean min max ZT0-3 0.354358 0.354358 0.354358 ZT4-7 0.20950924999999998 0.20950924999999998 0.20950924999999998 ZT8-11 0.853287 0.853287 0.853287 ZT12-15 7.71283 7.71283 7.71283 ZT16-19 14.205499999999999 14.205499999999999 14.205499999999999 ZT20-23 3.3716933333333334 3.3716933333333334 3.3716933333333334