Using Power Query to pull exchanges rates of different dates

Hi Anonymous ,

We can add a custom column using following formula and expand it to meet your requirement:

let
    url="https://www.xe.com/currencytables/?from="&[Currency]&"&date="&Date.ToText([Date],"YYYY-MM-DD"),
    CurrencyTable = Web.Page(Web.Contents(url)){0}[Data],
    SelectTable = Table.SelectColumns(CurrencyTable,{"Currency code ▲▼","Units per "&[Currency]}),
    Ta = Table.RenameColumns(SelectTable,{{"Currency code ▲▼","To Currency Code"},{"Units per "&[Currency],"Currency Number"}})
in  
    Ta

All the Query is here:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("Tc0xCsAgDAXQu2QWYjQWHdtaXEvFSbz/NRrTFgrhD//xSe9AYICslWw1SzpLCYmQAgzTwWk1eV9fjpjQWVUvDauW7fzGjP5RliaqHu36tuTklMP8vKjXkv/OMMYN", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Counter = _t, Amount = _t, Currency = _t, Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Counter", Int64.Type}, {"Amount", Int64.Type}, {"Currency", type text}, {"Date", type date}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "CurrencyHistory", each let  
                                                url="https://www.xe.com/currencytables/?from=" & [Currency]&"&date="&Date.ToText([Date],"YYYY-MM-DD"),
                                                CurrencyTable = Web.Page(Web.Contents(url)){0}[Data],
                                                SelectTable = Table.SelectColumns(CurrencyTable,{"Currency code ▲▼","Units per "&[Currency]}),
                                                Ta = Table.RenameColumns(SelectTable,{{"Currency code ▲▼","To Currency Code"},{"Units per "&[Currency],"Currency Number"}})
                                             in  
                                                Ta),
    #"Expanded CurrencyHistory" = Table.ExpandTableColumn(#"Added Custom", "CurrencyHistory", {"To Currency Code", "Currency Number"}, {"CurrencyHistory.To Currency Code", "CurrencyHistory.Currency Number"})
in
    #"Expanded CurrencyHistory"

If it doesn't meet your requirement, Please show the exact expected result based on the Tables that you have shared.

Best regards,