In a March survey rival Aquino had regained a significant nine-point lead.
On Thursday, the March survey of purchasing managers in the Chicago region is expected.
In the March survey, employment dropped an average of 1.9 percent.
Results of the March survey of the nation's purchasing managers showed conditions in the manufacturing sector remained very weak.
The March survey picked up a growing concern about inflation.
The numbers were based on a March 1995 survey of 55,000 households, bureau officials said.
The agency acknowledged some flaws in the March survey.
The latest count of 20.1 million Hispanics is based on a March 1989 survey of 58,000 households.
The group's analysis was based on a March 1994 survey by the Census Bureau in which 4,573 people were interviewed.
The average increase reported in the March survey was 8.5 per cent.