The Social Security Administration's average monthly benefit for a retired couple is about $3,120, totaling $37,440 annually. To privately match this income stream, a portfolio of approximately $800,000 to $936,000 is needed, based on different withdrawal strategies. However, replicating Social Security's inflation indexing feature, which adjusts benefits with the CPI, would demand a significantly larger portfolio, potentially around $2.23 million if using CDs at a 1.7% average yield.