Which investment performs best over the long term - shares, bonds, property? It's likely to be infrastructure: the airports, seaports and power supply and generation in Australia and overseas. But the problem for small investors is that infrastructure assets are big and lumpy.
Some infrastructure investments can be accessed via sharemarket-listed vehicles but the history of these holding toll roads in Australia is patchy. Most recently there was the failure of BrisConnections, Brisbane's airport link tunnel, with the operator going into receivership with $3 billion in debts.
But while infrastructure investment has been tainted by some flops among Australian toll roads, the 5 million members of industry super funds have done very well from the asset class.
These fund members own the fourth-largest water supply and sewerage company in England and Wales, a company that heats the homes of 4 million Poles, and airports overseas and in Australia. Such assets have helped give industry superannuation funds a long-term performance edge over retail funds. Such businesses seem diverse, but they have common characteristics.
They are usually essential services in which price increases do not reduce demand; often government-regulated to provide a service at an approved price; and tend to have high barriers to competition, such as regulations preventing a competing asset from being built close by.
Industry Funds Management, owned by 30 industry funds, is among the world's biggest owners of infrastructure assets. A few weeks ago it took a 35.5 per cent stake in the airport operator that owns Manchester Airport and London's Stansted Airport, as well as some smaller British airports.
Opportunities are emerging in Europe to buy good assets. Industry Funds Management global head of infrastructure Kyle Mangini says cash-strapped governments in the European Union are privatising all sorts of assets. An initiative in the European Union, for example, aims to sell assets in the energy space, particularly natural gas distribution.
Industry Funds Management has 45 investment executives globally who only buy and manage infrastructure assets.
"Infrastructure should provide good, steady, long-term returns," Mangini says.
"We should never do 30 per cent per annum."
The fund's infrastructure assets performed well during the global financial crisis and have produced low double-digit annual returns for the past 18 years. SuperRatings says non-profit funds, which include industry funds, have a return advantage over retail funds for the past 10 years of about 1.7 percentage points. That might not sound much, but compounded over 20 years in a fund member's super account, it adds up to a much bigger retirement nest egg.
The outperformance is not all down to infrastructure. Industry funds invest in other "alternative" asset classes - those outside the traditional ones of shares, bonds and cash - such as private equity. Industry funds also actively manage the asset allocation of their funds as investment conditions change, and they have low fees.