Flag of the United States
Since 1818, a star for each new state has been added to the flag on the Fourth of July immediately following each state's admission. In years in which multiple states have been admitted, the number of stars on the flag has jumped correspondingly. The greatest example so far was in 1890, when five states were admitted within the span of a single year (North Dakota, South Dakota, Montana, and Washington in November 1889 and Idaho on 3 July 1890). This change has typically been the only change made with each revision of the flag since 1777, with the exception of changes in 1795 and 1818, which increased the number of stripes to 15 and then returned it to 13, respectively.