Dalio breaks down his own strategy for taking on debt. : Many young people are deep in debt: Millennials between the ages of 25 and 34 have an average of $42,000 of debt per person and members of Gen Z (ages 16 to 20) already have an average debt of $4,343. And as interest rates rise, that debt is often becoming more expensive to pay off. Billionaire investor Ray Dalio, the founder of the world's largest hedge fund, Bridgewater Associates, advises young people to do a bit of analysis before they agree to take out a loan.