condition mean min max ZT0-3 5.931075 5.59441 6.26774 ZT4-7 4.028295 4.028295 4.028295 ZT8-11 1.403335 1.403335 1.403335 ZT12-15 0 0 0 ZT16-19 2.722035 2.722035 2.722035 ZT20-23 5.413845 5.413845 5.413845