Developed by Martin Zweig, the Puts/Calls Ratio
("P/C Ratio") is a market sentiment indicator that shows the
relationship between the number of Puts to Calls traded on the Chicago
Board Options Exchange (CBOE).
Traditionally, options are traded by
unsophisticated, impatient investors who are lured by the potential for
huge profits with a small capital outlay. Interestingly, the actions of
these investors provide excellent signals for market tops and bottoms.
Interpretation
A Call gives an investor the right to purchase 100
shares of stock at a pre-determined price. Investors who purchase Calls
expect stock prices to rise in the coming months. Conversely, a Put
gives an investor the right to sell 100 shares of stock at a pre-set
price. Investors purchasing Puts expect stock prices to decline. (An
exception to these general rules is that Puts and Calls can also be
purchased to hedge other investments, even other options.)
Because investors who purchase Calls expect the
market to rise and investors who purchase Puts expect the market to
decline, the relationship between the number of Puts to Calls
illustrates the bullish/bearish expectations of these traditionally
ineffective investors.
The higher the level of the P/C Ratio, the more
bearish these investors are on the market. Conversely, lower readings
indicate high Call volume and thus bullish expectations.
The P/C Ratio is a contrarian indicator. When it
reaches "excessive" levels, the market usually corrects by moving the
opposite direction. The following table, general guidelines for
interpreting the P/C Ratio. However, the market does not have to correct
itself just because investors are excessive in their bullish/bearish
beliefs! As with all technical analysis tools, you should use the P/C
Ratio in conjunction with other market indicators.
Table 12
P/C Ratio 10-day Moving Average
P/C Ratio 4-week Moving Average
Excessively Bearish (buy)
greater than 80
greater than 70
Excessively Bullish (sell)
less than 45
less than 40
Example
The following chart shows the S&P 500 and a 4-week
moving average of the Puts/Calls Ratio.
I drew "buy" arrows when investors were excessively
pessimistic (greater than 70) and "sell" arrows when they were
excessively optimistic (less than 40). The arrows certainly show that
investors are buying Puts when they should be buying Calls, and vice
versa.
Calculation
The Puts/Calls Ratio is calculated by dividing the
volume of Puts by the volume of Calls.