and the simple average of available data from 2002 to 2004 for “present” estimates. There are many gaps
in the calculations because the United States does not always import under every GTAP code from each
of the 17 partners. We fill in missing data with a preference for estimates from the same country but a
different year first, then from a nearby country with the same or nearby year, and lastly, with estimates
from a similar sector. The estimates of transportation costs are shown in tables A.67 through A.83.
Comparable data for the transportation costs on US exports (i.e., imports of the 17 partner
countries) would be cumbersome to evaluate if possible to find. We therefore make the assumption that
the change in transportation costs from “past” to “present” on US imports is identical to the change in
transportation costs on US exports from “past” to “present.”
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