To Mr. Inker, rigid adherence to the sector weightings of a market index would be a handicap.

He compares, for example, the sector weightings of the fund to those of the Russell index.

In addition to the twice-a-year reports to shareholders, the small-cap fund will disclose its top 10 holdings and its sector weightings each quarter.

All that information is used to choose his 170 to 200 stocks, matching the sector weightings of the S. & P. 500.

The index comprises three constituents each from five the five sub-sectors, with equal sector weightings.

The 100 top-ranked stocks make up the custom index, with the added requirement that sector weightings parallel the broader index.

Morningstar calculated its sector weightings as of Thursday by using funds' latest available portfolio disclosures.

Investors, he said, should focus on the sector weightings of their entire portfolios, not individual funds.

Generally, he keeps sector weightings within 50 percent, in either direction, of their levels in the index.

Most do just that and no more, though some issue lists of top holdings and sector weightings a bit more often.