"below addition by xxxx" not necessary Mark - keeping it unattributed is part of the deal. The record does show which user writes what though, and youd be wise to log in under a name (whatever it may be) to establish some sort of identity. This helps in a number of ways - including in our ability to talk to you through your talk page.
... African American, 0.06% Native American, 0.58% Asian, 0.00% Pacific Islander, 0.26% from other races, and 0.97% from two or more races. 1.88% of the population are ...