condition mean min max ZT0-3 5.918935 5.71874 6.11913 ZT4-7 5.106730000000001 5.106730000000001 5.106730000000001 ZT8-11 4.38137 4.38137 4.38137 ZT12-15 0 0 0 ZT16-19 5.555385 5.555385 5.555385 ZT20-23 4.518535 4.518535 4.518535