Most countries drive on the right-hand side of the road, but a minority use the left. Occasionally, countries switch sides, most famously Sweden in 1967 (Dagen H) and Samoa in 2009 (to align with its neighbors).

This market resolves to the next country that officially changes from left- to right-hand traffic, or from right- to left-hand traffic, based on a nationwide legal transition. Localized or partial changes (e.g. border crossings, new transit systems) do not count. The market resolves when the legal change takes effect.