Benchmark line in combo visual

Is there an easy way to add a benchmark line in a combo visual? 

Right now, an 85% benchmark is a bar (comparing against the bar total scores). The user wants to change it to a line. 

My second thought was to use the right total Invoiced YTD, gettinging the Max "total invoiced", then do 85% of the max, and apply it to each company. However, I was having difficulty building a measure with a constant value across all companies. 
FIrst, I have to figure out what the max (total invoiced YTD) across companies, which I can do, and put in a card visual (code 1 below). However, when I try to add that measure to the line axis, I get this error, because it seems PowerBI is trying to split the data back across companies: 

Code1: 

maxInvoicedItemsYTD = 
VAR yearBeginning =
    DATE ( YEAR ( MIN ( 'Date'[Date] ) ), 1, 1 )
VAR periodEnd =
    MAX ( 'Date'[Date] )
VAR InvoiceTotal =
MAXX(
    SUMMARIZECOLUMNS(
        Vendors[No],
        FILTER(
            ALL ( PurchaseInvoiceLine ),
            PurchaseInvoiceLine[PostingDate] >= yearBeginning
            &&PurchaseInvoiceLine[PostingDate] <= periodEnd
        ),
        FILTER(Vendors,Vendors[WTE Scorecard]=1),
        "TotalInvoiced",
        COALESCE ( SUM ( 'PurchaseInvoiceLine'[Amount] ), 0 )
    ),[TotalInvoiced]
)
return InvoiceTotal