What is Indexing?

Indexing is an investment practice that aims to match the returns of a specified market benchmark. An indexing manager or tracker attempts to replicate the target index by holding all or, with very large indexes, a representative sample of the securities in the index. Traditional active management is avoided with no investments made in individual stocks or industry sectors in an effort to beat the index. The indexing approach is often described as passive, emphasizing broad diversification, low trading activity and low costs.

Indexing as an investment practice has won acceptability in the last two decades as the mechanical outgrowth of a body of academic insights about markets and managers. Indeed, it was one of the first ideas to be propounded by finance academics from their empirical studies. These pointed out that the average manager would produce sub-average results due to expenses and above average managers would be identified and given more assets until they too became less than average. The system was the trap. After all, index accounts have prices set by all managers. In a sense, these accounts are the most managed of portfolios.

Indexing seems dull. Stock selection is done by a nameless committee at Standard & Poor's (S&P) or elsewhere for other indexes. Proportions are set by market prices, which are the aggregate wisdom of all participants. And administration is relatively simple because transactions are bunched together at the very instant at month end when the index composition may be rearranged.

In the late stages of the one-decision bull market of the 1960s, the idea of mechanically investing in the average just because it was the average would have failed. But in the mid-1970s, when a sharp market correction slayed the old gods and raised up new ones, it was just the thing. Nothing could challenge a roster of active, aggressive managers better than to have a mechanical bunny running the performance race with them and the bunny did not require dog food.