The timing is annual, but they're now considered a "reward" based on performance rather than a normal cost of living adjustment (which they never really were anyway at less than 3%). So it may or may not actually happen from one year to the next.
Annually and self review mandatory.
Answered - EA to COO, Prof. Dev. Div. (Former Employee) - Hoboken, NJ
Yearly, although not every year at this point.
Answered - Marketing (Former Employee) - Hoboken, NJ
Once a year, but employees have been informed that this is no longer guaranteed
Once a year.
Answered - Senior Copywriter (Former Employee) - San Francisco, CA