 The median age of the Mount Crosby population was 37 years of age.74.2% of people living in Mount Crosby were born in Australia, compared to the national average of 69.8%; the next most common countries of birth were England 7.2%, South Africa 3.2%, New Zealand 2.9%, United States of America 0.9%, Germany 0.8%.90.5% of people spoke only English at home; the next most common languages were 0.8% German, 0.6% Afrikaans, 0.5% Russian, 0.3% Persian (excluding Dari), 0.3% Mandarin.