Calculated column that checks whether a value in another column exists based on third value

You want to add a column for each month on your dataset is that it?

In this case you have two options:

Power Query

• Group your table by route and location
  • Select all rows in the option of aggregation

• Add a custom step that create a list based on month

Table.ToList (Table.SelectColumns ( [TableList], "Month"))

• Do merge with the Source step by location and route

• Expand the list from the table
• Add a custom step with the following code:

= List.Accumulate({"Jan", "Feb", "Mar", "Apr", "May", "June", "July","Aug", "Sep", "Oct", "Nov", "Dec"}, 
                                #"Expanded Added Custom1", (state, current) => 
                                Table.AddColumn(state, current, each if List.Contains( [Added Custom1.Custom], current) then "YES" else "NO"))

Result below:

Calculated Columns in DAX

For each month add the following column sintax:

July =
VAR routeselection = 'Table (2)'[Route]
VAR locationselection = 'Table (2)'[Location]
RETURN
    IF (
        "July"
            IN SELECTCOLUMNS (
                FILTER (
                    ALL ( 'Table (2)'[Route], 'Table (2)'[Month] ),
                    'Table (2)'[Route] = routeselection
                        && 'Table (2)'[Location] = locationselection
                ),
                "Months", 'Table (2)'[Month]
            ),
        "YES",
        "NO"
    )

You need to replace the name of the Month and the text after the IF

See attach PBIX file.