The size of Cethana is approximately 6.3 square kilometres. It has 5 parks covering nearly 63.3% of total area. The population of Cethana in 2006 was 398 people. By 2011 the population was 314 showing a population decline of 21.1% in the area during that time. The predominant age group in Cethana is 50-59 years. Households in Cethana are primarily childless couples and are likely to be repaying $600 - $799 per month on mortgage repayments. In general, people in Cethana work in a community and personal service occupation. In 2006, 82.7% of the homes in Cethana were owner-occupied compared with 80.1% in 2011.