From Wall Street to Main Street everyone has heard of the Dow Jones Industrial Average, the most closely quoted barometer of the US financial markets.

While professional investors scoff at the limited range of the 30-stock Dow, for more than 103 years individual investors around the world have continued to use it as a "health" index of the US economy; shunning the more professional, wider and perhaps more accurate S&P500.

Dow Dozen Does it

Ever since 1896 when Charles Dow first published his dozen stock index, it has tried to reflect what was happening in the wider economy.

Initially, that was agriculture and railroads.

Quaint names like American Cotton Oil, Distilling & Cattle Feeding and Tennessee Coal and Iron were among the first.

Some of the original dozen have gone bankrupt, two have been broken up in anti-trust actions and the rest have merged.

Only General Electric survives in its original form (and even that was kicked out for a time earlier in the century).

Smokestacks and autos

The 1920's saw the first major shift in emphasis to reflect the industrial power the United States was discovering.

General Motors arrived in 1915, Chrysler in 1928. Ironically, most of the companies now being kicked out also joined during this period of industrial growth.

Sears Roebuck was admitted in 1924, Union Carbide in 1928 and Goodyear and Chevron in 1930.

For more than 60 years they have reflected the strengths of the post-war American economic muscle.

Changes arrive

Changes after this burst have been slow to arrive. For years the Dow did not fully reflect the growth in financial services.

So, American Express only joined in 1982, JP Morgan in 1991 and the country's largest financial group Travellers (which includes Citibank and Salomon Smith Barney) arrived in 1997.

And for the past decade the call has been that the index lacked any serious attempt to reflect the technology sector, Hewlett Packard and IBM being the exceptions.

One problem was that most of the new high-tech companies were not quoted on the New York Stock Exchange, or The Big Board.

For, throughout its life, only NYSE shares have been chosen by the editors of the Wall Street Journal, who choose and compile the Dow.

The fastest and brightest tech companies were on the new Nasdaq exchange - off limits to the Dow until now.

The decision by the editors to include Microsoft and Intel will make the Dow certainly more reflective of what is happening in corporate America.

These are the new 'engines of growth' And now the virginity of the Dow has been broken other Nasdaq stocks will no doubt be considered.

There was, perhaps, one poignant reminder though that technology is not everything in America.