The length of time that a manager(s) has been at the helm of a mutual fund. A long-term fund performance record, preferably of five to 10 years, is a key indicator of a fund manager's investing abilities.

Mutual fund investors are best served by investment managers who have proved themselves over an extended period of time. The more closely matched a manager's tenure is with a solid fund performance record, the better.

For example, let's compare two different funds: The XYZ Fund has an annualized average 10-year total return of 11% and has been run by the same manager over that period. The ABC Fund has the same 10-year annualized average total return of 11%, but it has had two different managers. One's tenure covered the first nine years and the second has only been on the job for one year. Will the second manager be just as good as the first? We hope so, but making a decision on current managerial quality is difficult because fund performance and managerial tenure don't match.

For obvious reasons, mutual funds under team management or index funds are not subject to questions concerning manager tenure.