Show HN: The "Lost Decade" for investors: did you make money or lose money?

They say that the first decade of this century was the "Lost Decade" for investors: the stock market ended flat. Say your portfolio ended flat as well. Does that mean your money was "flat," that is, you neither made or lost money? Of course not. You put in money along the way. Depending on when and how, you could have made or lost a lot. Pretty much anything is possible. We made a tool that shows you what happened: greaterthanzero.com