public static function getDirSizeCount($dir)
    {
        if (!is_dir($dir)) {
            throw new RuntimeException(sprintf('Invalid directory path supplied "%s"', $dir));
        }

        $count = 0.00;
        $iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($dir));

        foreach ($iterator as $file) {
            $count += $file->getSize(); 
        }

        return $count;
    }