A huge source of confusion among Veterans is how ratings are combined for different disabilities to determine what the overall disability picture is. The way disabilities are added is not a simple addition problem. There is no attempt to explain exactly how it works because its easiest to be referred to the relevant regulation. When there are two or more service-connected disabilities, the overall percentage of disability is calculated by combining the individual ratings, but not by adding them together. To determine the proper combined rating, the VA makes a calculation by considering each disability in order of severity, beginning with the highest evaluation. Detailed instructions on how to make these calculations and the “Combined Rating Table” are contained in the VA regulations. 38 C.F.R. 4.25. There is a rule against anti pyramiding, that is basically a prohibition against compensating a veteran more than once for the “same disability” or the “same manifestation” such as for impairments in the knee or some other anatomical region. In some cases you can argue that they are separate impairments even if in similar region. Bilateral factor the individual disability ratings are for when bilateral disabilities will be combined as usual, and then 10 percent of the value of the combined rating will be added. 38 C.F.R. 4.26. The additional 10% is the bilateral factor and will be added before any additional non bilateral disabilities are figured into.