Measure Capability in Dataflows

See this ScottBrown 
it does a series of calculations in the Dim Date Table with some self-merges of different steps. It returns these  columns. Your date table has more than the fiscal table, so not everything is there - no 2018 for example.

You can see in the steps I broke it into two areas as there needed to be a different way to get fiscal period vs Year status.

The file is here https://1drv.ms/x/s!AheFG2CwN3xnivI023Lxboobm6MVwQ?e=VOzs2N

 

If that isn't what you want, and you cannot modify my code to suit your needs, please provid a mock up in excel of the desired results.

 

I think this is what you want ScottBrown 

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwMlHSUVKK1QGzjYFs/4LUPBjfCI1vCOR7ZBaXYPJjAQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Year = _t, Status = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Year", Int64.Type}}),
    AddedMinYear =
        Table.AddColumn(
            #"Changed Type",
            "Min Year",
            each
                List.Min(
                    Table.SelectRows(#"Changed Type", each [Status] = "Open")[Year]
                )
        )
in
    AddedMinYear

Your general idea was right, but the syntax was off.
For this table this works fine, but this logic will not work at all in a table with a few thousand records. Power Query is horrible at table scans like this. DAX is what works best, but for 3 records or even 300, Power Query is fine.