The big picture is: the main thing you should be concerned about in the future are incremental returns on capital going forward. As it turns out, past history of a good return on capital is a good proxy for this but obviously not foolproof. I think this is an area where thoughtful analysis can add value to any simple ranking/screening strategy such as the magic formula. When doing in depth analysis of companies, I care very much about long term earnings power, not necessarily so much about the volatility of that earnings power but about my certainty of "normal" earnings power over time.

Value investing strategies have worked for years and everyone's known about them. They continue to work because it's hard for people to do, for two main reasons. First, the companies that show up on the screens can be scary and not doing so well, so people find them difficult to buy. Second, there can be one-, two- or three-year periods when a strategy like this doesn't work. Most people aren't capable of sticking it out through that.

Look down, not up, when making your initial investment decision. If you don’t lose money, most of the remaining alternatives are good ones.

The way we make money as a group is that we don't pay a lot for anything, and most of the stocks we buy have low expectations.

I don't know too many people that are good at timing the market relative to macro-economic events.

Figure out what something is worth and pay a lot less.

The big picture is: the main thing you should be concerned about in the future are incremental returns on capital going forward. As it turns out, past history of a good return on capital is a good proxy for this but obviously not foolproof. I think this is an area where thoughtful analysis can add value to any simple ranking/screening strategy such as the magic formula. When doing in depth analysis of companies, I care very much about long term earnings power, not necessarily so much about the volatility of that earnings power but about my certainty of "normal" earnings power over time.