condition mean min max ZT0-3 2215.215977 2215.215977 2215.215977 ZT4-7 1768.098017 1768.098017 1768.098017 ZT8-11 1939.5074525 1939.5074525 1939.5074525 ZT12-15 2102.386377 2102.386377 2102.386377 ZT16-19 1871.64478 1871.64478 1871.64478 ZT20-23 2228.72927 2228.72927 2228.72927