Why, beacused ISM change the formula for its calcultion. But market sold off 3%, so I expect mkt to rally back next week, hard !! http://www.bloomberg.com/apps/news?pid=20601087&sid=a2VGaRdrKS3Q&refer=home ..."New Measure Today's U.S. services report included a new composite index to reflect changes in current measures of business activity, new orders, employment and supplier deliveries. The contribution from each sub-index is equal. The new composite index was 44.6 in January. It would have been 53.2 in December, according to Bloomberg calculations based on a formula provided by ISM. "...
The new calculation was announced in advance, though. Bloomberg and other places had already written about it. It was no surprise. It was still a very poor ISM number, even the market over-reacted a little.