 The median age of the Mount Crosby population was 39 years of age.72.9% of people living in Mount Crosby were born in Australia, compared to the national average of 66.7%; the next most common countries of birth were England 6.9%, South Africa 3.3%, New Zealand 2.9%, Germany 1.1%, United States of America 0.7%.90.6% of people spoke only English at home; the next most common languages were Afrikaans 1.1%, German 1%, Mandarin 0.8%, Dutch 0.4%, Persian (excluding Dari) 0.4%.