How can I properly interpret the returns chart?

In four steps:

• Set your risk profile first. At the top you select a profile. Higher risk generally means more equities, so more chance of high returns and of larger interim drops. All figures adjust accordingly.
• Look at the annual returns. Each bar is one calendar year. Watch the average across years and the spread between good and bad ones.
• Look at cumulative growth. This line shows how a one-off contribution would have developed. This is where compounding becomes visible.
• Keep the context in mind. The charts are based on historical data, not a forecast.

Past performance is no guarantee of future results. See current figures on the returns page or read about the compounding effect.