Volumes could be written on the bending and breaking of rules that accompany investment managers' track records. Here, the investment performance record is manipulated by the manager's inclusion of only selected accounts in the data. An example is survivorship bias, where historical performance is reported only for those accounts still with the firm. In this ploy, when an account cancels, its performance history is removed from the advisor's record. The advisor's advertised record is truly reflective of the remaining accounts, but not reflective of the entire spectrum of the advisor's results.
Some advisors are more blatant in their reporting selectivity.
They hand pick a single outstanding account or a handful of their best performing accounts during a given year as their official record. The selected account or group is often altered to include only the best performing among the advisor's client base in a given year. Banks' advisory arms and trust departments often practice another form of selective reporting. They have several different pools of managed assets in the form of commingled trust funds, separately managed trusts, commingled institutional funds, and separately managed institutional funds. The commingled funds may be further subdivided by differing objectives.