Ago date or time - Time ago/Day ago

Ago date or time - Time ago/Day ago 

"year+month+day+time ago"  PHP function

Function to format the comment post times in the ever trendy "time ago" style... such as; posted 6 months 3 weeks ago;
<?php
function time_ago($date,$granularity=2) {
    $date = strtotime($date);
    $difference = time() - $date;
    $periods = array('decade' => 315360000,
        'year' => 31536000,
        'month' => 2628000,
        'week' => 604800,
        'day' => 86400,
        'hour' => 3600,
        'minute' => 60,
        'second' => 1);
    if ($difference < 5) { // less than 5 seconds ago, let's say "just now"
        $retval = "posted just now";
        return $retval;
    } else {                           
        foreach ($periods as $key => $value) {
            if ($difference >= $value) {
                $time = floor($difference/$value);
                $difference %= $value;
                $retval .= ($retval ? ' ' : '').$time.' ';
                $retval .= (($time > 1) ? $key.'s' : $key);
                $granularity--;
            }
            if ($granularity == '0') { break; }
        }
        return ' posted '.$retval.' ago';     
    }
}


//call a function here
echo $date = time_ago('2011-04-22 16:59:06');?>