Create Counter for Each Value in a Specific Columns as New Columns

This was cool,

You should to pivot the Category column.
This is the new script:

let
Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjDVNzDXNzIwNFfSUXJOLElNzy+qNFSK1QFKmZEmZQSRMkeSwhRBM8cCi5QxRMoS3RxDA5zmYJUywi0FtCIWAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Date = _t, Categories = _t]),
#"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type date}, {"Categories", type text}}),
#"Replaced Value" = Table.ReplaceValue(#"Changed Type","","""Null""",Replacer.ReplaceValue,{"Categories"}),
#"Duplicated Column" = Table.DuplicateColumn(#"Replaced Value", "Categories", "Categories - Copy"),
#"Pivoted Column" = Table.Pivot(#"Duplicated Column", List.Distinct(#"Duplicated Column"[#"Categories - Copy"]), "Categories - Copy", "Categories", List.Count)
in
#"Pivoted Column"

I deserve a big congratulation, so I congratulate myself ... Well done ...; D