Index values in MPI data

[TiffanyPressler]

My company purchased some ESRI MPI data last year for internet usage.  The data lists each survey question twice - one column for Buyers and one column for "Index."  Can someone please tell me what the "Index" value represents?  The data is only for one state, not the whole country...

Thanks!

[Jason_RobinsonRobinson]

I have attached an image which provides and explanation of what an Index is.  If you have any questions just let me know.