Railroad carloads traffic is a good "real" indicator of economic activity in the United States. The one-year moving sum of total carloads oscillated between about 320,000 units to 350,000 units from 1989 to 2008. Since 2008, however, has been between about 260,000 units to 290,000 units.
Encouragingly, the year-over-year change in the 4-week moving average is at the highest percentage change since early 2012.
This increase in traffic has been helped by the two month rebound in petroleum products carloads. The chart below clearly shows the effect of the shale oil revolution in the United States.