We’ll be covering this topic in February.
This chart forecasts of traffic (you’ll learn about trends, and forecasting, and about applying those to GDP … and this will help with the first two). Each year, a new forecast of traffic is made, dependent on the current amount of traffic.
You should try to identify 1) whether these forecasts are based on the assumption that traffic has a deterministic or stochastic trend, and then 2) consider what that assumes about the ability and willingness of drivers to change their behavior.
The source article is here. It is not required reading.