Number client rows in table

Hi Anonymous 

Try this script or see the attached.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("bY7BDcMwDAN38TsCSDm141kC779GqTpVU7TPI46UzrOwOR5lKw7DYQ4eAgyjL5jbxyEyltMNe8D4cjTyjgXN1Pl1esY67NdoOtwVV95u+fjroBoidqwCGMB0olpx/fPa6cu57UTMlvOCukCjcz4B", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Clientnumber = _t, #"Begin date" = _t, #"End date" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Clientnumber", Int64.Type}, {"Begin date", type date}, {"End date", type date}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Clientnumber"}, {{"tbl", each  
        let 
            tbl = _,
            #"Sorted Rows" = Table.Sort( tbl, {{ "End date", Order.Ascending } } ),
            #"Added Index" = Table.AddIndexColumn(#"Sorted Rows", "Clientcount", 1, 1)
        in 
            #"Added Index", type table }}),
    #"Expanded tbl" = Table.ExpandTableColumn(#"Grouped Rows", "tbl", {"Begin date", "End date", "Clientcount"}, {"Begin date", "End date", "Clientcount"}),
    #"Changed Type1" = Table.TransformColumnTypes(#"Expanded tbl",{{"Begin date", type date}, {"End date", type date}, {"Clientcount", Int64.Type}})
in
    #"Changed Type1"

Hi Anonymous ， 

You could refer to Mariusz 's suggestions, and you also could refer to my sample for details.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("bY7BDcMwDAN38TsCSDm141kC779GqTpVU7TPI46UzrOwOR5lKw7DYQ4eAgyjL5jbxyEyltMNe8D4cjTyjgXN1Pl1esY67NdoOtwVV95u+fjroBoidqwCGMB0olpx/fPa6cu57UTMlvOCukCjcz4B", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Clientnumber = _t, #"Begin date" = _t, #"End date" = _t]),
    #"Replaced Value" = Table.ReplaceValue(Source,"-",".",Replacer.ReplaceText,{"Begin date", "End date"}),
    #"Changed Type with Locale" = Table.TransformColumnTypes(#"Replaced Value", {{"Begin date", type date}, {"End date", type date}}, "sq-AL"),
    #"Grouped Rows" = Table.Group(#"Changed Type with Locale", {"Clientnumber"}, {{"all", each _, type table [Clientnumber=text, Begin date=date, End date=date]}}),
    #"Added Custom" = Table.AddColumn(#"Grouped Rows", "client count", each Table.AddIndexColumn([all], "client count", 1,1)),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"all"}),
    #"Expanded client count" = Table.ExpandTableColumn(#"Removed Columns", "client count", {"Begin date", "End date", "client count"}, {"Begin date", "End date", "client count.1"})
in
    #"Expanded client count"

Best Regards,
Zoe Zhi

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