Converting ranking into percentage of maximum

[Swartkat75]

Hi there

I am super novice and trying to convert a ranking of train stations - in this example 1 to 84 (based on their level of tree coverage) - to percentage. I.e. The highest-ranking station is 84 so his percentage ranking will be 100%. 84/84.

I just don't know how to right the DAX formula to do this?

This is how far I have come: 

RANKING SCORE = DIVIDE('URBAN ECOLOGY Measure - Urban_tree_canopy_coverage'[RANKING],84)

I would like to know what the correct DAX is to refer to the MAx Ranking measure, instead of just plugging the number in, 84.

I have done this conversion in Excel and added the column to check if the formula works ("SCORE - Urban tree canopy coverage").

[wdx223_Daniel]

countrows(allselected(table[station precinct])

??

[Swartkat75]

I have progressed slightly with this formula: 

RANKING SCORE = DIVIDE('Table'[RANKING],max('Table'[RANKING]))

Using the MAX function rather than reference the measure (MAx Ranking = max(Table[Ranking)].