condition mean min max ZT0-3 10.1756825 9.31849 11.032875 ZT4-7 7.909815 7.909815 7.909815 ZT8-11 8.36261 8.36261 8.36261 ZT12-15 0 0 0 ZT16-19 10.95965 10.95965 10.95965 ZT20-23 8.5923 8.5923 8.5923