Bash progress bar

function ProgressBar
{
    let _progress=(${1}*100/${2}*100)/100
    let _done=(${_progress}*4)/10
    let _left=40-$_done
    _fill=$(printf "%${_done}s")
    _empty=$(printf "%${_left}s")
printf "\rВыполнение : [${_fill// /#}${_empty// /-}] ${_progress}%%"
}

ProgressBar $actual_value_var $max_value_var