Premise: Household mail is defined as the sum of mail in the above three sectors and is shown as Subtotal in Table 1. Its annual growth rate fell from 6.6 percent in 1987-90 to 0.7 in 1990-93 and further to negative 1.4 percent in 1993-97.

Hypothesis: Household mail is the sum of mail in two sectors.
Relation: contradiction