condition mean min max ZT0-3 0.503873 0.503873 0.503873 ZT4-7 0.2199925 0.2199925 0.2199925 ZT8-11 0.477426 0.477426 0.477426 ZT12-15 1.9546700000000001 1.9546700000000001 1.9546700000000001 ZT16-19 1.33737 1.33737 1.33737 ZT20-23 1.142497 1.142497 1.142497