Investing $500 every month at a 7% average annual return grows to $609,985 in 30 years. You contribute $180,000 in total, and compound interest adds $429,985.

Key Numbers

• •Total after 30 years at 7%: $609,985
• •Total contributions: $180,000
• •Interest earned: $429,985
• •Starting with a $10,000 lump sum as well: $691,150