Samoa Cancelled Dec. 31st last year

Chart from Rarotonga, Cook Island to American ...

There was no Dec. 31st in Samoa in 2011. At midnight on Dec. 30th, the country switched to the western side of the International Dateline (to be date-aligned with China, its main trading partner), thus setting the date to Jan. 1st instead of Dec. 31st. (via Discovery News). I wonder how many Samoans missed a Dec. 31st birthday.