$re = '/.* ([^a-z]+)$/im';
$str = 'Job number 45752 Subtotal price $937.50
Job number 7852 Subtotal amount $637.50
Job number 42 Subtotal test $427.50
Job number 47592 Subtotal sample $976.50 ';
$subst = "$1";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php