condition mean min max ZT0-3 48.837012 48.837012 48.837012 ZT4-7 41.186605 41.186605 41.186605 ZT8-11 38.9452785 38.9452785 38.9452785 ZT12-15 32.2453575 32.2453575 32.2453575 ZT16-19 21.126063000000002 21.126063000000002 21.126063000000002 ZT20-23 19.71717 19.71717 19.71717