mediately after war was declared, however, traffic began to decline, at first in anticipation of shortages and later in response to actual shortages and governmental restrictions on the purchase of automobiles, tires, and gasoline. Figure 11 shows for the eastern, central, and western sections of the country a comparison of highway traffic on rural roads in each month of 1942 and 1943 with that in the corresponding month of 1941. The effective dates of important restrictions affecting traffic are indicated on the chart Throughout the 2 years, relative traffic declines were greatest in the East and least in the West. Nation-wide rationing, which became effective about the 1st of December 1942, brought the curves almost together, temporarily, but the curve for the western section soon rose and continued well above that for the eastern section.
As can be seen in figure 10, traffic started rising in 1944, even though the war was not yet over; and upon the cessation of hostilities rose very rapidly until, in 1948, it was back to the level it would have attained if the upward prewar trend had continued without interruption.
Table 3 gives the vehicle-miles of travel on all rural roads and city streets in each year from 1941 to 1948, inclusive, and the relation to 1941 travel of that of each subsequent year. The decline of traffic from 1941 to 1943 was 42 percent on rural roads and 33 percent on city streets. The reason for the greater decline on rural roads is undoubtedly that a higher proportion of the traffic on them was recreational and nonessential, while a larger proportion of the urban traffic was to and from work and for other essential purposes.
