Codewars: Largest Difference in Increasing Indexes

gistfile1.txt

var largestDifference = function(data) {
  var diff = data.length - 1,
      i;
  
  while(diff > 0) {
    for(i = 0; i + diff < data.length; i++) {
      if (data[i] <= data[i + diff]) {
        return diff;
      }
    }
    diff--;
  }

  return 0;
};