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looking for research tool to plug in and evaluate theoretical historical returns
The professional financial advisors do have tools which will take a general description of a portfolio and run monte-carlo simulations based on the stock market's historical behavior. After about 100 simulation passes they can give a statistical statement about the probable returns, the risk involved in that strategy, and their confidence in these numbers.  Note that they do not just use the historical data or individual stocks. There's no way to guarantee that the same historical accidents would have occurred that made one company more successful than another, or that they will again. "Past performance is no guarantee of future results"... but general trends and patterns can be roughly modelled. Which makes that a good fit for those of us buying index funds, less good for those who want to play at a greater level of detail in the hope of doing better. But that's sorta the point; to beat market rate of return with the same kind of statistical confidence takes a lot more work.