condition mean min max ZT0-3 1.8818199999999998 1.8818199999999998 1.8818199999999998 ZT4-7 1.773785 1.773785 1.773785 ZT8-11 1.367195 1.367195 1.367195 ZT12-15 2.606345 2.606345 2.606345 ZT16-19 4.57028 4.57028 4.57028 ZT20-23 2.8635900000000003 2.8635900000000003 2.8635900000000003