The size of Simson is approximately 5.9 square kilometres. It has 1 park covering nearly 36.8% of total area. The population of Simson in 2011 was 501 people. By 2016 the population was 78 showing a population decline of 84.4% in the area during that time. The predominant age group in Simson is 60-69 years. Households in Simson are primarily childless couples and are likely to be repaying $1000 - $1399 per month on mortgage repayments. In general, people in Simson work in a trades occupation. In 2011, 80.1% of the homes in Simson were owner-occupied compared with 71% in 2016.