condition mean min max ZT0-3 20.757619 20.757619 20.757619 ZT4-7 16.210537000000002 16.210537000000002 16.210537000000002 ZT8-11 14.8165595 14.8165595 14.8165595 ZT12-15 16.218933500000002 16.218933500000002 16.218933500000002 ZT16-19 17.699872 17.699872 17.699872 ZT20-23 17.1670835 17.1670835 17.1670835