let
Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
#"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", Int64.Type}}),
#"Split Column by Position" = Table.SplitColumn(Table.TransformColumnTypes(#"Changed Type", {{"Date", type text}}, "en-US"), "Date", Splitter.SplitTextByPositions({0, 4}, true), {"Date.1", "Date.2"}),
#"Split Column by Position1" = Table.SplitColumn(Table.TransformColumnTypes(#"Split Column by Position", {{"Date.1", type text}}, "en-US"), "Date.1", Splitter.SplitTextByPositions({0, 2}, true), {"Date.1.1", "Date.1.2"}),
#"Merged Columns" = Table.CombineColumns(#"Split Column by Position1",{"Date.1.1", "Date.1.2", "Date.2"},Combiner.CombineTextByDelimiter("/", QuoteStyle.None),"New Date"),
#"Changed Type1" = Table.TransformColumnTypes(#"Merged Columns",{{"New Date", type date}})
in
#"Changed Type1"