condition mean min max ZT0-3 3.8339749999999997 3.8339749999999997 3.8339749999999997 ZT4-7 3.997615 3.997615 3.997615 ZT8-11 3.4996 3.4996 3.4996 ZT12-15 3.4566850000000002 3.4566850000000002 3.4566850000000002 ZT16-19 5.48132 5.48132 5.48132 ZT20-23 4.66179 4.66179 4.66179