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Q: The volume of letters sent by households or household originated mail can be obtained from Table 1 by adding the volumes of HH-to-HH and HH-to-NHH mail. In 1997, households originated only 16 percent of First-Class mail, down from 23 percent in 1990.
A:
The volume of letters sent by households or household originated mail can be obtained from Table 1 by adding the volumes of HH-to-HH and HH-to-NHH mail.