Dev
 US            Bra            1949         x3
> US            Can            1949        x4
> US            Can            1950        x5
> US            Can            1951        x6
> US            Col             1950        x7
> US            Chile           1950        x9
> US            Mex            1950        x10
> Arg            Bra             1950        x11
> Arg            Can            1951        x12
>
>
> Arg           US              1950        x1
> Arg            US             1951        x2
>
>
> Chile        Mex             1952        xN
>
>
> Mex        US                1950        x10
If you have country1 and country2 information in 2 separate data sets,
would -joinby- solve your problem?
Stephen
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