code: public long getTotalSavings() {
  		long totalSavings = 0;
  		for (OptimizerResult result : results) {
  			totalSavings += (result.getOriginalFileSize() - result.getOptimizedFileSize());
  		}
  
  		return totalSavings;
  	}
docs: Get the number of bytes saved in all images processed so far
  
  @return The number of bytes saved