Advisors who are looking for, say, a domestic equity ETF for a portfolio will want to examine potential candidates to see which fund best suits the client's needs. Aside from checking the basic rules governing the underlying index, you'd probably want to compare the expense ratios, number of holdings, sector breakdowns, top holdings with percentages, and yields.

Good luck with that.

If you are considering just a few candidates, you may find everything you need with one visit to each sponsor's website. But because the various sponsors report inconsistently and often with delays, it's hard to get a clean comparison between rival offerings.

STALE COMPARISONS

More likely, you will have to make multiple visits just to obtain the desired metrics for a single point in time. Your efforts could actually take several weeks, depending on the ETF providers you are considering.

And when you're finished, you could have a stale comparison.

If you aren't looking for the information exactly when the ETF companies are releasing it, you may have to compare the yield from the end of the previous month for one ETF against yesterday's yield from another fund. Or one fund's holdings may be up to date while another's are from the end of last month.

It's an understatement to call these “apples and oranges” comparisons. A better analogy would be fruit salad.

For the most part, expense ratios are fairly stable. When there is a change, ETF providers say they post it promptly. But what about those other metrics?

DAILY UPDATES? NOT LIKELY

Only three of the top 10 ETF companies by assets -- Invesco PowerShares, State Street and WisdomTree -- update all of the previously mentioned statistics daily for their basic domestic equity portfolios.

Here's how the others fund sponsors update each of the stats for their domestic equity ETFs. I excluded inverse and geared funds.

Number of holdings: First Trust, Guggenheim, iShares, Schwab and Van Eck all update the number of holdings daily. And ProShares lists all holdings daily, but doesn't number the list, so you have to count it yourself or drop it into an Excel file. Vanguard posts the number of holdings 15 days after the end of the calendar month. This is because all Vanguard ETFs are classes of its traditional index mutual funds, a Vanguard spokesman says, and the delay protects long-term investors from traders who may try to front-run trades made for index reconstruction.

Sector breakdown: First Trust, iShares, and ProShares provide daily sector breakdowns of their equity portfolios. Guggenheim lists some ETF sector breakdowns daily, but others quarterly. Schwab posts sector breakdowns from three to nine business days after the end of the month. Van Eck updates sector weightings monthly a week into the new month. Vanguard posts sector breakdowns monthly with a 10-day delay, for the reason cited above.

Top holdings with percentages: First Trust, Guggenheim, iShares, and Schwab show the top 10 holdings (with percentages) daily. As noted earlier, ProShares lists all its holdings daily, along with the dollar value of each position -- but it doesn't give the percentage of the portfolio represented. (You can download the holdings to an Excel file, however, and do your own calculations.) Van Eck lists all holdings and percentages daily, but you'll have to look at the entire holdings list to see that. The section of the website marked "top 10 holdings" is updated monthly with a one week delay. Vanguard reports monthly with a 15-day delay.

30-day SEC yield: Some advisors may prefer a different measure of yield, but at least this metric is standardized. Reporting of it isn't, though. Schwab, Van Eck, and Vanguard post daily. Guggenheim updates weekly, but doesn't post yields under 2%. ProShares updates monthly, three business days into the new month. For iShares equity ETFs, the number arrives five business days after month's end. And First Trust updates monthly within seven business days of the end of the month.

NOT SO TRANSPARENT

Since ETFs have always been marketed as transparent investments, advisors may wonder why all metrics are not posted daily.

Vanguard cites protection of long-term investors as the reason for delaying its reporting. Yet many competitors provide information daily and still seem to be able to deal with attempts by traders to front run.

Other ETF companies cite “industry standards” or delays by data providers, compliance departments, or custodians as the reasons for not posting certain numbers daily. But it is clear that data can be delivered daily if there is a will to do so.

Perhaps if advisors and investors, the customers of ETF companies, insist on timely data, they will get it.

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