Chemical said it wanted to reduce its expenses to 57 percent of its revenues.
Chemical said it expected the deal to be consummated on Jan. 1.
Chemical said its new rate on the six-month account was 6.85 percent, up from 6.77 percent.
Like other banks, Chemical says it is taking the problem seriously.
Chemical said it intended to complete the merger later this month.
Chemical says only 5 percent of its customers closed accounts after losing their branches.
Chemical said it would provide $600 million of that amount.
After three months, Chemical returned to 6 1/2 percent and said the lower rate had not attracted much new business.
Chemical said it was considering these and other possible responses.
Chemical said it was offering 14 million common shares at $31.25 a share, the proceeds of which would be used for general corporate purposes.