REUTERS/Todd Korol
Economists had estimated that the composite index climbed to -3.5 in July, after a print of -7 for June.
So far this year, the index has been on the decline.
The gauge of manufacturing activity in the region includes a survey to assess business leaders' outlook.
In the wake of the oil crash, many respondents reported a hit to their businesses, directly or indirectly, although one respondent in last month's report said the worst may be over.