condition mean min max ZT0-3 43.171677 43.171677 43.171677 ZT4-7 26.4629675 26.4629675 26.4629675 ZT8-11 17.300316000000002 17.300316000000002 17.300316000000002 ZT12-15 16.4608715 16.4608715 16.4608715 ZT16-19 15.1852865 15.1852865 15.1852865 ZT20-23 15.72589 15.72589 15.72589