condition mean min max ZT0-3 2.38927 2.38927 2.38927 ZT4-7 1.499735 1.499735 1.499735 ZT8-11 2.11835 2.11835 2.11835 ZT12-15 2.464735 2.464735 2.464735 ZT16-19 2.989985 2.989985 2.989985 ZT20-23 2.6550000000000002 2.6550000000000002 2.6550000000000002