condition mean min max ZT0-3 1.27771 1.27771 1.27771 ZT4-7 1.15211 1.15211 1.15211 ZT8-11 1.739445 1.739445 1.739445 ZT12-15 1.64093 1.64093 1.64093 ZT16-19 1.7427000000000001 1.7427000000000001 1.7427000000000001 ZT20-23 1.21668 1.21668 1.21668