The Breadth Thrust

Marty Zweig (1942-2013) was a highly successful securities trader and investment adviser with a net worth and lifestyle to show for it.

Throughout the 1980s, he was regular on Louis Rukeyser's acclaimed PBS show Wall Street Week — in its day the highest-ranked show on PBS — even ahead of Sesame Street.

Marty went to Wharton, earned a PhD in Finance from Michigan and developed numerous tools for analyzing market direction and investment selection.  The one thing they all had in common was that they were quantitative - data based.

He is credited with the phrase, "Don't fight the Fed"  and, on a now famous Wall Street Week show that aired on Friday, October 16 announced that he felt very uneasy about the market - three days before the 1987 crash.

Perhaps his most famous tool is the remarkable Breadth Thrust Indicator — remarkable for the fact that it is quite rare, but has been highly accurate over many decades.

​The ingredients and formulas are well known:

We begin with:

10-Day simple moving average of the ratio:

NYSE Advancing Issues / Total of NYSE Advancing and Decliniing Issues

Then we subtrtact:​

Same ratio ten trading days earlier

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