IPART determines the maximum rate of return on investment regulated businesses may earn using the WACC methodology. WACC is the weighted average of debt and equity costs.
We have developed a standard way of determining WACC in our reviews. In addition to our pricing reviews, we publish a six-monthly update of the market data used to calculate WACC. We also publish estimates of the market risk premium (MRP) MRP estimates at end April 2017.
We also publish Monthly time series of individual MRP estimates from July 2008 to July 2017.
IPART is currently reviewing its methodology for setting the weighted average cost of capital (WACC). We expect to release a final report for our review in early 2018.