Aggregation on Matrix

Hi Guys,

I am trying to aggregate a measure on a matrix column. This is what it looks like now. But I want it to be aggregated as you go up the matrix

I am using the following measure :

Costo Oportunidad = 

var precio_producto =

    LOOKUPVALUE(
        DM_productos[pvp],
        DM_productos[simi_code],
        SELECTEDVALUE(
            DM_productos[simi_code]
        )
    )

return

IF(
[Brecha]<0,
[Brecha] *-1*precio_producto
)

 Thanks,

Reynaldo