Thank you very much for your quick reply.
I always click okay but have never seen the result.
I forgot to mention that originally I had [Original_Week] field as a string ('2017-W01', '2017-W02', '2017-W03'....). In data manager, I clicked on edit the original table and created a new field, called Week, as Num(Right(Original_Week,2). If I select any Week in the filter, the original bar chart (Sum(Sales) vs Country) is filtered properly. For that reason, I don't think it should be the problem.