condition mean min max ZT0-3 1.448385 1.448385 1.448385 ZT4-7 1.150805 1.150805 1.150805 ZT8-11 2.450675 2.450675 2.450675 ZT12-15 2.0629999999999997 2.0629999999999997 2.0629999999999997 ZT16-19 3.411225 3.411225 3.411225 ZT20-23 1.6189200000000001 1.6189200000000001 1.6189200000000001