condition mean min max ZT0-3 91.293835 91.293835 91.293835 ZT4-7 79.336034 79.336034 79.336034 ZT8-11 74.644272 74.644272 74.644272 ZT12-15 85.896953 85.896953 85.896953 ZT16-19 67.45023 67.45023 67.45023 ZT20-23 63.7123105 63.7123105 63.7123105