// Creation of a calendar from nothing
let
Source = List.Numbers( 41270, 5000),
// create a list of 5000 days as from day 41270 (27th Dec 2012)
// this goes until 4th Sept 2026
// at that time the start point should be changed or the calender should be made longer (5500 days or 6000 days)
#"Converted to Table" = Table.FromList(Source, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
#"Changed Type" = Table.TransformColumnTypes(#"Converted to Table",{{"Column1", type date}}),
#"Renamed Columns" = Table.RenameColumns(#"Changed Type",{{"Column1", "dday"}})
in
#"Renamed Columns"