Calculate value between two dates

Hi Anonymous 

You can do it in Query Editor like below 
Price table

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WclTSUTI0MACSBob6QGRkYGgJ5BgDOcYQTqwOVJUpTJUJTJVSbCwA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [#"Product Code" = _t, Cost = _t, startDate = _t, endDate = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Product Code", type text}, {"Cost", Int64.Type}, {"startDate", type date}, {"endDate", type date}})
in
    #"Changed Type"

Quantity table

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WclTSUTIw1Dcw0jcyMLQEcgyVYnUQwqYwYSMUYTMk1bEA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Product = _t, date = _t, #"number of Products" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Product", type text}, {"date", type date}, {"number of Products", Int64.Type}}),
    #"Added Custom" =Table.AddColumn(#"Changed Type", "Cost", each let d = [date] in Table.SelectRows(ProductPrice, each [startDate] <= d and (if [endDate] <> null then [endDate] >= d else true))[Cost]),
    #"Expanded Custom" = Table.ExpandListColumn(#"Added Custom", "Cost"),
    #"Changed Type1" = Table.TransformColumnTypes(#"Expanded Custom",{{"Cost", type number}})
in
    #"Changed Type1"

Regards,
Mariusz

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