This graph is important in my eyes as it shows that over the long term you will nearly always make more than 4% p.a. if invested in equities, the probability of not achieving the hurdle rate of 4% is close to zero, as shown by the turquoise line. It also shows that the probability of not achieving 4% p.a. with bonds is close to 100% over the long term as shown by the bright red line. People investing in „safe“ bonds (or cash for that matter) will always underperform people investing in equities over the long term.