condition mean min max ZT0-3 3.2206625 2.805035 3.63629 ZT4-7 2.7120699999999998 2.7120699999999998 2.7120699999999998 ZT8-11 1.6245949999999998 1.6245949999999998 1.6245949999999998 ZT12-15 0 0 0 ZT16-19 1.5280900000000002 1.5280900000000002 1.5280900000000002 ZT20-23 3.30347 3.30347 3.30347