Migration helps balance our ageing population – we don't need a moratorium

Australia’s population is set to reach 25 million in the coming weeks. This is much earlier than expected. Eighteen years ago, projections estimated Australia’s population wouldn’t get to 25 million until 2041.

Western Australian Liberal Senator Dean Smith last week proposed a moratorium on immigration to give Australia some time to “breathe” and take stock. Claiming concerns over planning and infrastructure failing to meet population needs, Smith signalled Australia was unprepared, having relied on inaccurate population projections.

Immigration is often targeted when population levels seem out of control. But will a moratorium give Australia the supposed breathing space it needs?

Read more: FactCheck: is Australia's population the 'highest growing in the world'?

Migration impacts

Concerns about immigration and a perceived population crisis have crossed over the spectrum of Australian politics. One Nation’s Pauline Hanson has called for a plebiscite on immigration, while Labor leader Bill Shorten has raised concerns about the number of temporary migrants in Australia.

Immigration Minister Peter Dutton has said a cut to immigration numbers would have economic benefits, contradicting Treasurer Scott Morrison. And Smith’s idea to halt immigration to allow the nation’s infrastructure time to catch up with population demand is shared by prominent public figures, including Bob Carr and Dick Smith.

Australia’s population is ageing, which has potential adverse consequences for the future as proportionally more people exit the workforce, increasing reliance on a shrinking income taxpayer base. Immigration has the potential to offset these consequences of population ageing by contributing to the workforce and to government funds for essential services. Migrants also contribute to Australia’s future population by having children.

The latest available research suggests immigration levels at “about 160,000 and 210,000 seem to have the ‘best’ impact by 2050 on ageing of the population and the rate of growth of GDP per capita”.

Read more: Bloom and boom: how babies and migrants have contributed to Australia's population growth

Current ABS projections provide an opportunity to examine what Australia’s demographic composition could look like if net overseas migration was zero, 200,000 (low), 240,000 (middle) or 280,000 (high) per year.

Based on 2011 census data, and medium-range assumptions for fertility and life expectancy, the 2013 (medium range) projections are tracking well with current estimates. These projections provide an indication of the impact of migration, measured as net overseas migration. Net overseas migration reflects the balance of incoming and outgoing movements and includes both permanent and temporary migration.

The four ABS scenarios show varying population numbers over the medium to long term. The higher the net overseas migration level, the bigger the population over the projected years. Interestingly, though, while zero net overseas migration would result in a reduction in population by the year 2070, the population would still continue to grow in the medium term due to natural increase (births minus deaths).

Population composition is an important indicator to consider, rather than size alone. Age distribution is essential to understanding the fiscal opportunities and challenges a population faces.

Comparing the four net overseas migration scenarios illustrates the important contribution migration makes to Australia. The so-called dependency burden – the ratio of the number of children (0-14 years old) and older people (65 years or over) to the working-age population (15-64 years old) – is higher for zero and low net migration levels.

The current rate of net migration provides the middle ground in balancing population age structure and growth.

Population projections

Planners need to know expected population size and growth to ensure adequate services and provisions. The ABS has produced projections for national and sub-national populations since 1950.

Population inquiries throughout Australia’s history have consistently called on such statistics to enable the country’s responsiveness and preparedness to accommodate numbers. Australia hasn’t set any population targets, mainly to avoid coercive population measures (such as mandating birth rates) and to allow flexibility in government policy, particularly around immigration intake.

Read more: Australia doesn't have a population policy – why?

Estimating population size and growth into the future is about what might be (projection) and not what will be (forecast). So population projections are not predictions; they’re calculations of potential future populations based on assumptions about possible births, deaths and migration.

The “best-before-date” for population projections is considered to be around 5-10 years from the initial base year of calculation. This is why projections should be regularly updated based on best available population data (the census and vital statistics) to ensure assumptions reflect births, deaths and migration trends.

Australia is one part of the global community. Cutting immigration to Australia will impact the demographic composition of the country, with consequences for the working-age population and income tax base.

Any changes to the migration program should be considered alongside evidence. Available evidence shows Australia’s current migration program intake (190,000) is about right for Australia.

Australia doesn’t need a moratorium. What we need is a respectful, open and evidence-based population discussion.