Is MEAN for Data set a different formula than regular Mean?

I have a problem w/ chips stacks at. 195K 196k,205k,210k,212k,210k,205k,199400,201k,197k,192 k,190k..

I came up w/ the Mean of $201,033 but I was told there was a different formula for Data sets? Help please. Thanks

[jaydub]

I do not understand your question. Do you have several data sets with different numbers of elements and those data sets individually have the means you listed?