Price-to-Sales (P/S) Ratio for the S&P 500 Index

The Price-to-sales ratio can be calculated for a single stock of an index. It is calculated by dividing the current market value by the revenues (sales) of the last 12 months.

High P/S ratios indicate an overvaluation of the market, low P/S ratios a bear market. This notion has not changed, but the ratio values have increased in the last years. 

In the 1950’s crisis, at the market peak, the P/S was 1.08 in 1956, and at the market low, it was 0.89 in 1957. 

In the 2000’s crisis, at the market peak, the P/S was 2.44 in 2000, and at the market low, it was 1.31 in 2003. However, it came back to about 1.6 in 2007 and then fell to 0.8 in 2009.

In short:

  • P/S Ratio can be calculated for single stocks and for indices
  • P/S Ratio is the price of the company on the market divided by revenue of the last 12 months
  • P/S Ratio is regular between 1-2, Above 2: high, below 1: low, this is strongly depending on history and context and cannot be applied universally

The Theory Behind the Price to Sales Ratio

Price-Earnings-Ratios are a common indicator for stocks and markets. However, they can be poor valuation indicators in periods where profits decrease. 

For example in 1991, the P/E ratio reached 20 because profits sunk. However, stocks were entering a new bull market. In October 2002, at the low dot-com bubble, PE ratios were above 30, anyways it was the moment to buy as the bear market reached its bottom. 

This is what we already saw in our previous article about the P/E ratio.

A graph that shows the P/E ratio and related crises

Also, the P/E ratio can be influenced by companies cutting costs and going for short term profitability and returns, especially through increased margins.

Therefore, the Price-to-Sales ratio is an indicator that can give additional information when the P/E is not working.

How to Use the Price to Sales Ratio?

Just as P/E ratios, P/S ratios had different values at peaks and bottoms of the market. Looking at the table below, you can see the major peaks and bottoms of the S&P500 since 1955. 

As we can see, there is no clear pattern of a fixed number that indicates a high or a low. Rather the context has to be seen. Markets in 1981 peaked at a P/S ratio 0.52 and they bottomed at 0.54 in 1973. On the other hand, markets peaked at 1.37 in 1961 and bottomed at 1.31 in 2003.

Price to Sales Peaks and Troughs for S&P 500
Date PeakP/S PeakDate TroughP/S Trough
Apr 6, 19561.02Oct 25, 19600.89
Jan 8, 19601.18Oct 28, 19601.06
Dec 15, 19611.37Jun 29, 19621.02
Feb 11, 19661.32Oct 7, 19661.00
Dec 6, 19681.27May 29, 19700.83
Apr 30, 19711.10Nov 26, 19710.96
Jan 1, 19731.11Dec 6,19740.54
Sep 24, 19760.67Mar 3, 1978 0.49
Sep 8, 19780.60Apr 25, 19800.49
May 1, 19810.52Aug 13, 19820.40
Dec 2, 19830.62Jul 27, 19840.56
Aug 28, 19870.99Oct 23 19870.74
Jul 20, 19900.85Oct 12, 19900.72
Jul 17, 19982.04Aug 4, 19981.67
Mar 24, 20002.44Mar 14, 20031.31

The level of the P/S is also depending on the general profitability of the market. If the market is highly profitable, a higher P/S ratio makes sense. This becomes especially clear, when we look at single stocks of highly profitable companies, they can be over 4 and well priced. 

Stocks of companies with little profitability can have a P/S of as low as 0.25 which might be a correct market pricing. The following graph shows the P/S ratio of the last two crises (dot com bubble 2000-2002, housing bubble 2007-2009) where we see higher P/S ratios than in the past.

A graph that shows the price to sales ratio from 1990 to 2018
Image Source

Up-to-date data for the P/S ratio of the S&P 500 can be found here