Fund managers and super funds with high fees claim that it's not fees that matter, but the returns after fees.
And they are right. It's the money after fees, costs and taxes - that which ends up in your pocket that matters.
There are examples of high-fee super funds that do leave their investors with good net returns.
But fees matter more than they let on. That's because it's just so hard to predict which super fund is going to do well.
And even when a fund has a period of good returns, it can find it very difficult to keep producing good returns over extended periods.
The higher the fees the higher the hurdle over which the fund has to jump in order to leave more in your pocket.
Fees are known and something over which you have control; as you can choose a low-fee fund, whereas the investment performance of a fund is outside of your control.
The default options, the balanced investment options where most people have their money, have asset allocations with a lot of similarities. However, the devil is in the detail as many better performers have higher exposures to property, private equity and infrastructure.
Still, the returns, before fees, tend to be fairly close around the median over the long term.
With super, over time, the fees and costs compound and really eat into the returns.
Super funds have different types of fees. One is a flat-dollar administration fee, typically several dollars a week. And there's an investment management fee that is charged as a percentage of the super account balance.
I asked researcher SuperRatings to crunch the numbers to test if there is a link between fees and returns.
SuperRatings ranked 113 balanced investment options on its database by returns over five years.
The investment management fees are similar across the board - so that is not something that fund members have to be too concerned with.
The big differences among the balanced investment options are with the administration fees they charge.
The SuperRating's analysis shows balanced options in the bottom 25 per cent of performers over the past five years, with a typical average annual compound return of 8 per cent, have the highest administration fees of, on average $348, and a total fee of $758.
On the other hand, the top 25 per cent of performers have a typical return of 10.3 per cent, with an average administration fee of $162 and a total fee of $498.
Going with a super fund purely on the basis of a low administration fee will not guarantee above average returns.
Some high-fee funds have good performances. But there is a correlation, at least on these five-year numbers, where lower administration-fee funds, on the whole, do better than high-fee funds with the same investments.
Given the importance of fees, it's all the more surprising that three out of five super fund members told a recent poll, by comparison site Finder, they have no idea of what fees they are paying.
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The story Why it's important to know what fees you are paying on super first appeared on The Sydney Morning Herald.