Multiply column by standard rate

Dears,

I have two tables. First is sales data divided by months, years, and countries. Second table is country with standard multiplier. I have to multiply sales data from first table by standard multiplier from second table. Each month from first table has to be multiply by standard multiplier from second table. Both tables can be linked only by country. 

Issue is if i merge both tables by country and i simple create measure to multiply sales by multiplier, multiplier is sum and i get totally wrong result.

Thank you

Michal