The alpha of a fund is a measure of the investment performance on a risk-adjusted basis, relative to a benchmark.
What does the chart show?
The chart shows how a fund’s alpha has varied based on the rolling period selected. An alpha above zero generally indicates the fund has outperformed the benchmark on a risk-adjusted basis, conversely an alpha less than zero generally indicates that the fund has under performed the benchmark on a risk-adjusted basis. The selection of a benchmark is critical to this analysis, to ensure a like for like comparison.
When to use the chart
The chart provides a useful comparison between similar funds and can indicate which fund has demonstrated a consistent outperformance over the benchmark over a selected investment horizon. Lonsec notes that alpha should be used in conjunction with other risk measures (especially the beta analysis to ensure the benchmark selection is appropriate) when identifying funds.