Fiscal Week

Hi StephenGW ,

Please try the following code:

let
// Enter the date in Advanced Editor for the first day of the earliest Fiscal Year in #date(yyyy,m,d) format
StartDate = #date(2021, 1, 3),
// Enter the desired range of years as List in Advanced Editor
YearRange = {2021..2050},
// In Advanced Editor, use one of the two options for this step (code out the one not used with //) to either hard code or dynamically calculate the years with 53 weeks. Substitute a different evaluation criterion as needed.
YearsWith53Weeks = {2020},
//YearsWith53Weeks = List.Select(YearRange, each Date.DayOfWeekName(#date(_,11,30)) = "Saturday"),
StartingTable = Table.FromColumns({YearRange}, {"Year"}),
AddNumberOfWeeksColumn = Table.AddColumn(StartingTable, "Weeks", each if List.Contains(YearsWith53Weeks, [Year]) then 53 else 52),
#"Changed Type4" = Table.TransformColumnTypes(AddNumberOfWeeksColumn,{{"Year", Int64.Type}, {"Weeks", Int64.Type}}),
// In the Advanced Editor, enter the two patterns for 52 and 53 week years as a list of weeks per fiscal month
AddListOfMonthAndWeekCounts = Table.AddColumn(#"Changed Type4", "Custom", each if [Weeks] = 53 then List.Zip({{1..12}, {4,4,5,4,4,5,4,4,5,4,5,5}}) else List.Zip({{1..12}, {4,5,4,4,5,4,4,5,4,4,5,4}})),
#"Expanded Custom" = Table.ExpandListColumn(AddListOfMonthAndWeekCounts, "Custom"),
#"Extracted Values" = Table.TransformColumns(#"Expanded Custom", {"Custom", each Text.Combine(List.Transform(_, Text.From), ";"), type text}),
#"Split Column by Delimiter" = Table.SplitColumn(#"Extracted Values", "Custom", Splitter.SplitTextByDelimiter(";", QuoteStyle.Csv), {"FM", "NumWeeks"}),
#"Changed Type" = Table.TransformColumnTypes(#"Split Column by Delimiter",{{"FM", Int64.Type}, {"NumWeeks", Int64.Type}}),
AddListOfWeeksColumn = Table.AddColumn(#"Changed Type", "WeekInFM", each {1..[NumWeeks]}),
#"Expanded Custom1" = Table.ExpandListColumn(AddListOfWeeksColumn, "WeekInFM"),
#"Changed Type1" = Table.TransformColumnTypes(#"Expanded Custom1",{{"WeekInFM", Int64.Type}}),
    #"Grouped Rows" = Table.Group(#"Changed Type1", {"Year"}, {{"All", each _, type table [Year=nullable number, Weeks=nullable number, FM=nullable number, NumWeeks=nullable number, WeekInFM=nullable number]}}),
    #"Added Custom" = Table.AddColumn(#"Grouped Rows", "Custom", each Table.AddIndexColumn([All], "New FW Index", 1)),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"Year", "All"}),
    #"Expanded Custom2" = Table.ExpandTableColumn(#"Removed Columns", "Custom", {"Year", "Weeks", "FM", "NumWeeks", "WeekInFM", "New FW Index"}, {"Year", "Weeks", "FM", "NumWeeks", "WeekInFM", "New FW Index"}),
AddWeekIndex = Table.AddIndexColumn(#"Expanded Custom2", "FW_Index", 1, 1, Int64.Type),
Add7DayListPerWeek = Table.AddColumn(AddWeekIndex, "WeekDay", each {1..7}),
#"Expanded WeekDay" = Table.ExpandListColumn(Add7DayListPerWeek, "WeekDay"),
#"Changed Type2" = Table.TransformColumnTypes(#"Expanded WeekDay",{{"WeekDay", Int64.Type}}),
RemoveUnneededColumns = Table.RemoveColumns(#"Changed Type2",{"Weeks", "NumWeeks", "WeekDay"}),
AddDayIndex = Table.AddIndexColumn(RemoveUnneededColumns, "DayIndex", 0, 1, Int64.Type),
AddDatesBasedOnStartDateAndDayIndex = Table.AddColumn(AddDayIndex, "Date", each Date.AddDays(StartDate, [DayIndex]), type date)
in
AddDatesBasedOnStartDateAndDayIndex

If the problem is still not resolved, please provide detailed error information or the expected result you expect. Let me know immediately, looking forward to your reply.
Best Regards,
Winniz
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