The S&P 500 averages something like 7-8% over a 20 year timeline. Index funds tracking it will return similar performance. I would imagine Patrick is providing

The S&P 500 averages something like 7-8% over a 20 year timeline. Index funds tracking it will return similar performance. I would imagine Patrick is providing a conservative estimate, because regardless of the market average you can't count on seeing $80k on $1M each year.