Samoa skipped December 30, 2011, when it moved west across the International Date Line and changed time zones.
Before the change, Samoa’s civil time was 21 hours behind UTC. At the end of December 29, 2011, clocks jumped forward, and the next calendar date became December 31. The shift placed Samoa on the same side of the date line as important trading partners such as Australia and New Zealand, so its working week would align more closely with theirs.
The change created a memorable New Year’s Eve sequence: Samoa celebrated December 31 after having no December 30 that year. It was a change to the civil calendar, not an alteration of the astronomical length of the day. The neighboring territory of American Samoa made the opposite practical transition, so the two Samoas became separated by a calendar day even though they are geographically close.