Generating $20,000 per month (equivalent to $240,000 per year) in passive investment income depends heavily on the target portfolio dividend yield or asset return rate. Assuming a balanced, conservative portfolio yielding an average annual return of 5%, an investor would require approximately $4.8 million in capital. Alternatively, achieving that cash flow through higher-yielding instruments averaging 8% to 10% would still necessitate a principal investment between $2.4 million and $3 million.