condition mean min max ZT0-3 0.8462151666666667 0.526953 1.0280165 ZT4-7 0.940471 0.940471 0.940471 ZT8-11 1.069576 1.069576 1.069576 ZT12-15 1.1155490000000001 1.038713 1.192385 ZT16-19 1.46836 1.46836 1.46836 ZT20-23 1.4944700000000002 1.4944700000000002 1.4944700000000002