Like oxygen, reports on the daily doings of the Dow Jones Industrial Average are everywhere. It's the fastest way to check Wall Street's pulse and the one benchmark most likely to be quoted in the morning paper and the nightly news.

There are 30 companies which comprise the DJIA and with Dow-member GE likely to acquire another Dow member, Honeywell, there may soon be a slot open for another Goliath on the famed top-30 list.

Once the new firm is named, its stock will then be integrated into the current system and DJIA movements up or down will continue to be reported as if nothing has happened.

But that's not the case. Each and every time Dow membership changes it makes sense to wonder if we are still comparing apples with apples.

Started in 1896 with 12 stocks, the DJIA has risen from a first-year close of 40.45 to 10,946.72 as of February 7, 2001. Over a period of 105 years, that's an average annual increase of 5.58 percent and a fabulous argument for the joys of compound interest.

But within that general average are a series of ups and downs. The DJIA hit 41.22 in 1932, essentially back where it began in 1896. The benchmark 300 recorded at the end of 1928 was not seen again until 26 years later when the Dow closed for the year at 404 in 1954. The yearly close didn't top 500 until 1958 and it wasn't until 1972 that the year-end average finally reached 1000.

Between 1896 and 1981 the Dow grew by an annual average of 3.68%, but between 1982 and 1999 the measure increased at year-end from 1046 to 11497, an average growth of 15.14%.

The catch, of course, is that while the percentages and numbers above are accurate, what they measure has shifted over time.

As it happens, the modern Olympics also began in 1896. Thomas Burke of the U.S. won the 100-meter race in 12 seconds flat. In the 2000 Olympic races just held in Sydney, Maurice Greene covered the same distance in 9.87 seconds.

It's possible to compare the efforts of Burke and Greene because there's a common measure: 100 meters is 100 meters. We know with total assurance that Greene is astonishingly faster than Burke.

Alas, the Dow averages from 100 years ago, 20 years ago, and even five years ago track stocks that differ from the ones we watch today, thus comparing results with one period or another requires a whole bunch of asterisks and caveats.

To faithfully track stock movements from 1896 or within any period we need a consistent measure. But the only stock from 1896 found on today's DJIA is General Electric. One can only guess how the average would look at this time if the DJIA still accounted for American Cotton Oil, Distilling & Cattle Feeding, and U.S. Leather.

And that, of course, is the core point. Companies come and go, investing preferences evolve, and if we are to track marketplace trends then we should not ignore either the great successes or those firms which have become less favored.

For instance, whatever happened to such DJIA stalwarts as U.S. Cordage (added in 1896), Standard Rope & Twine (1896), Federal Steel (1899), Central Leather (1912), Studebaker (1916), Corn Products (1920), Woolworth (1924), Paramount Famous Lasky (1925), Remington Typewriter (1925), Nash Motors (1928), Postum (1928), Victor Talking Machine (1928), and Hudson Motors (1930)? If we are to fully reflect the path of American commerce, then surely we must account for the direction, destiny, and descendants of these firms. (For a look at the companies which have composed the DJIA over the years, see such excellent histories as those provided by Equity Analytics, BrainBank, and USA Today.)

In 1998 the Dow was revised still again. Such new-economy giants as Intel, Microsoft, and Home Depot were added to the list, while Sears, Goodyear, and Union Carbide were dropped. The new firms are surely significant, but how many people no longer shop at Sears or reject tires from Goodyear? Did these firms suddenly disappear from the pantheon of corporate America?

To have a consistent set of benchmarks, why not evolve a series of DJIAs? In the same way that Super Bowl XXX I inevitably follows Super Bowl XXX, why not acknowledge that the DJIA of the moment is not measuring the same body of information as the DJIA from 1995, 1930, or 1900? All good years -- but all different.

And so a modest proposal. Let us anoint today's GE and Honeywell-endowed DJIA as "DJIA-1." When next we add or subtract company members because they merge, fail or somehow become less interesting, we can move on to "DJIA-2." To have a clear and consistent accounting of what it is that we're measuring, we can then post the averages for each index each day and easily compare one period with another.

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