condition mean min max ZT0-3 8.471668333333334 2.9085900000000002 11.91925 ZT4-7 3.0114 3.0114 3.0114 ZT8-11 3.61731 3.61731 3.61731 ZT12-15 6.256645000000001 4.55837 7.95492 ZT16-19 12.06155 12.06155 12.06155 ZT20-23 15.590699999999998 15.590699999999998 15.590699999999998