assigning rank to array keys

${'stats' . $run} = array
  (
  "AP"=>$AP,
  "EP"=>$EP,
  "SP"=>$SP,
  "FX"=>$FX,
  "Horse"=>$horse,
  
  );
  $allstats[] = ${'stats' . $run};

I have that running in a while loop to add an array to the main one every time it goes through it. However, my issue is I am trying to assign ranks for each value. Saw horse 1 had AP=51 , EP=47, SP= 32, FX=20. Horse 2 had AP=52, EP = 55, SP=30 and F=19. I am trying to make it print on the screen like so:

                      AP   EP   SP   FX  

Horse 1           2      2     1     1

Horse 2           1      1     2     2

And etc for however many horses there are.

Any ideas or help would be much appreciated. Thanks