Total kilometer length of expressways as defined below.
An expressway is a divided highway for high-speed traffic with at least partial control of access. The degree of
access allowed varies between countries and even between regions within the same country. In some jurisdictions,
expressways are divided arterial roads with limits on the frequency of driveways and intersecting cross-streets. In other jurisdictions, access to expressways is limited only to grade-separated interchanges, making them the full equivalent of freeways. (Wikipedia)