Future inventory level

Hi, carmae 

Yes, if you want to group and accumulate data, you only need to go one more step to group by Item.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("fdIxDsMgDIXhuzCnAmxCyBF6hihjx269v8ryiBKePaJPWGD9xxHev883hyWkFiVHSVL6IadwLncT2Esn02FlsgJbJ1rHNZmsOiM35ynNubcPq0/TZL9Fx1rksZY9pmzd6yaOqfWHbtbKOl0rm606IzfnKc2Zea0sDxOnFhirBcZqgZGvg1gtMFYLjNUCY7XAWC3i1AJjtYhTC4zVAmO1wKyVGbXAWC0wVguM1QK71XL+AQ==", BinaryEncoding.Base64), Compression.Deflate)), 
    let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Item = _t, #"Date Item" = _t, Quantity = _t]),
    
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Item", type text}, {"Date Item", type date}, {"Quantity", Int64.Type}}),
    FX = (values as list) as list =>
        let
            GRTList = List.Generate(
                () => [GRT = values{0}, i = 0],
                each [i] < List.Count(values),
                each 
                    let
                        nextGRT = if [GRT] > 0 then [GRT] + values{[i] + 1} else values{[i] + 1}
                    in
                        [GRT = nextGRT, i = [i] + 1],
                each [GRT]
            )
        in
            GRTList,
 
    // Group by Item and apply transformations
    Grouped = Table.Group(
        #"Changed Type",
        {"Item"},
        {
            {"Transformed", each 
                let
                    dateitemlist = List.Buffer([Date Item]),
                    quantitylist = List.Buffer([#"Quantity"]),
                    result = Table.FromColumns(
                        {dateitemlist, quantitylist, List.Transform(FX(quantitylist), each if _ < 0 then 0 else _)},
                        {"Date Item", "Quantity", "Output"}
                    )
                in
                    result
            }
        }
    ),
    #"Expanded Transformed" = Table.ExpandTableColumn(Grouped, "Transformed", {"Date Item", "Quantity", "Output"}, {"Date Item", "Quantity", "Output"})
in
    #"Expanded Transformed"

Best Regards,
Yang
Community Support Team

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