condition mean min max ZT0-3 38.0 38.0 38.0 ZT4-7 50.3 50.3 50.3 ZT8-11 46.0 46.0 46.0 ZT12-15 64.05 64.05 64.05 ZT16-19 50.050000000000004 50.050000000000004 50.050000000000004 ZT20-23 16.9 16.9 16.9