The unknown is whether these two inflation barometers have positive surprises - as they did in March - or negative ones.

Another key inflation barometer that remains far from the danger zone is the price of gold, which is supposed to rise with inflationary expectations.

This week's data, from home sales and consumer confidence to the gross domestic product and inflation barometers, might not be threatening in a calmer environment.

The decline in the widely watched inflation barometer was the largest since Sept. 26, 1980, when the index plunged 6.80 points.

The rally yesterday was helped along in the afternoon by declines in other inflation barometers that traders watch closely.

Two other inflation barometers, worker productivity and unit labor costs for the fourth quarter, are due on Thursday.

It said the mistake in the retail price index, the main inflation barometer, went undetected from February 1986 until October of this year.

More important, both inflation barometers, excluding food and energy, are expected to show a climb of a moderate 0.2 percent for April.

Those snippets are from the index for personal consumption expenditures, an inflation barometer favored by the Fed.

The index, a widely watched inflation barometer, fell for the first time in seven months.