Just a self updating copyright year range

functions.php

<?php

/**
 * Copyright Years
 * Outputs an years range based on specified year to current year
 * 
 * @param	int	$copyYear	- the year since the copyright starts (should be lower than current year)
 * @return 	string	- a range of years (eg. "2000-2010")
 */
function copyright( $copyYear ) {

	$curYear = date( 'Y' );
	$copyYear = is_int( $copyYear ) ? $copyYear : $curYear;
	$copyright = $copyYear . ( ( $copyYear != $curYear && $copyYear < $curYear ) ? '-' . $curYear : '');

	return $copyright;
}