custom command line to get the realtime percentage of transfered files (in size not file number)

size_of_your_source_folder=`du -s  /path/to/your/source/folder` && clear && while true; do echo -ne "$(echo "scale=4;`du -s /path/to/your/dest/folder | awk '{print $1}'` / $size_of_your_source_folder * 100" | bc)%\r"; sleep 2; done

/dirtycode