A lag in the movement of the Monthly Treasury Average has the index still on the decline even as Treasury yields have been on the rise.
Data reported by the Federal Reserve Board indicate that the MTA was 0.15917 percent during the month of June.
That was lower than in May, when the index was 0.16333 percent.
But the MTA has increased from the same month last year. At that point, the index was 0.14750 percent.
The MTA has fallen each month since February, when it came in at 0.17750 percent.
The index is calculated by taking a 12-month average of the daily average for the yield on the one-year Treasury note.
In June, the daily average for the one-year Treasury yield was 0.14 percent, up from 0.12 percent in May.
While the MTA is used an index on some adjustable-rate mortgages, a much more popular ARM index is the yield on the one-year Treasury note.
The Department of the Treasury reported the one-year Treasury yield at 0.15 percent as of the end of June, up from 0.14 percent at the end of May.
The one-year Treasury yield, which had been as low as 0.10 percent in May, closed at 0.15 percent Monday.
ARMs accounted for 8.1 percent of all pricing inquiries in the U.S. Mortgage Market Index report from LoanSifter and Mortgage Daily for the week ended June 28.
