PHP: date to age

gistfile1

<?php

/* Date to Age */

if(
	isset ($data['day']) && isset($data['month']) && isset($data['year']) && 
	is_numeric($data['day']) &&
	is_numeric($data['month']) &&
	is_numeric($data['year'])
){
    $birth 			= strtotime($data['year'].'-'.$data['month'].'-'.$data['day']);
    $age_in_seconds = time() - $birth;
    $age 			= floor($age_in_seconds / 31556926); // 31 556 926 seconds in year
    
}else $age = 'undetermined';

echo $age;

?>