code: public String formatMillisPerOperation(int theNumOperations) {
  		double millisPerOperation = (((double) getMillis()) / Math.max(1.0, theNumOperations));
  		return formatMillis(millisPerOperation);
  	}
docs: Returns a nice human-readable display of the time taken per
  operation. Note that this may not actually output the number
  of milliseconds if the time taken per operation was very long (over
  10 seconds)
  
  @see #formatMillis(long)