what risk does someone with $5m confront of not seeing 2% ($100,000) annual return (before tax, adjusting for inflation) for the next 40 years? i ask because i

what risk does someone with $5m confront of not seeing 2% ($100,000) annual return (before tax, adjusting for inflation) for the next 40 years? i ask because i'm going to spend the next hour or so fantasizing about being in the ops position.