Oct. 31 (Bloomberg) -- U.S. stock investors have been more fearful for longer than they were in the weeks before the October 1987 market crash, according to a gauge known as the old VIX.

The CHART OF THE DAY shows the closing values for this indicator, the Chicago Board Options Exchange S&P 100 Volatility Index, in the past two months (the white line) and the same period 21 years ago (the red line).

This year, the old VIX climbed from the start of September through Oct. 11, when it surpassed 100 in intraday trading for the first time since the month of the crash. Back in 1987, the index stayed below 30 until the Friday before stocks tumbled.

The indicator is derived from prices of options on the S&P 100, as its name suggests. The current version, introduced five years ago, uses S&P 500 options and includes more contracts in the calculations. Their readings tend to be similar. The VIX closed yesterday at 62.90.

In 1987, the old VIX behaved differently than it has this year because the plunge in stocks was ``a far quicker affair,'' Michael Shaoul, chief executive officer of Oscar Gruss & Son Inc., wrote yesterday in an e-mail. ``There was nothing like the same degree of economic problems at the time and no concerns about the global banking system outside of the fact that equity markets had crashed.''

The old VIX peaked at 103.41 on Oct. 11 as the S&P 100 swung between a 3.2 percent gain and an 8.1 percent loss. The high was well below its record of 172.79 on Oct. 20, 1987, the day after the so-called Black Monday crash.

During October 1987, the index exceeded 100 for seven days in a row. It then fell for nine consecutive months and returned to the mid-20s, in line with its pre-Black Monday readings.

To contact the reporter on this story: David Wilson in New York at dwilson@bloomberg.net

Last Updated: October 31, 2008 11:07 EDT