Kinda surprised this hasn't been mentioned but just FYI... Raises are PERCENTAGES based on your overall review score...
Overall you can get something like: Outstanding, Exceeds Expectations, Excellent, Meets Expectations, ect (cant remember the names)
THEN each overall score has a percent linked to it.. most scores fall between 3.5-4.5%
Example: You get an Excellent and it's 4% this year (each yeah the % changes but its the same % for everybody). If you're making $10.00/hr you would multiply that by .04 and your raise would be 40 cents, meaning you'd now be getting $10.40. If you're making $11/hr with an Excellent score, you'd get a 44 cent raise.
It's that simple. They don't just throw darts and give you a random number... BUT your overall score might be random, based on everything and anything. Keep in mind there's only a certain amount of scores they can give out, only a COUPLE people get the TOP 'Outstanding' score, most fall in the middle around excellent