Create Groups of Equal Size

ANBILY1 
Below is the correct code which dynamically group the code and based on that it splits the table.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("xdExDoAgEAXRu2yNCaAolC57C8L9ryEdGKe3oHkhcT62Jj5swW/RxyRO7nGku6ERdUc9UBPqiXqhZtRCOojurtsUtyluU9ymuE1/+tr6khVfsmKZYZlhmWGZYZlhmWHZ1IxaSF//eCpuC99t/QE=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, Code = _t, Value = _t]),
    TypeChanged = Table.TransformColumnTypes(Source,{{"Date", type date}, {"Code", type text}, {"Value", type text}}),
    Result = Table.Combine( 
let
CodeGrouping =
Table.Group(
TypeChanged,{"Code"},{"AllRows", each _ }
)[AllRows],
SplitTable =
List.Combine(
List.Transform( 
CodeGrouping,(x) =>
Table.Split(x,5)
) ),
Result =
List.Transform( 
SplitTable,(x) =>
let
RowCountAdded =Table.AddColumn(
    x,"RowCount",each Table.RowCount(x) ),
ListOfDatesAdded = 
Table.AddColumn(RowCountAdded,"Dates",each RowCountAdded[Date]),
DateRemoved = 
Table.SelectColumns(ListOfDatesAdded,
List.Select(Table.ColumnNames(ListOfDatesAdded), each _ <>"Date") ),
RemoveDuplicate = 
Table.Distinct(DateRemoved)
in 
RemoveDuplicate
)
in 
Result
)
in
    Result

I have imported more 12 rows as Code D. It dynamically groups and split the table as 5 rows. Below screenshot

one suggesation, please do not use List.FirstN if you are dealing with large data.. It technically slow  down the query performance.

Attaching the file for your reference.

Hope it helps

Regards,

sanalytics