WordPress | Dynamic copyright with current year and site title plus tagline

copyright.php

<?php
$build_year = '2018'; // Amend this accordingly using the YYYY format
$year = date('Y'); // Get A full numeric representation of the current year, 4 digits
$blogname = get_bloginfo( 'name' ); // Get the Site Title as specified in Settings / General
echo '<p class="copyright">&copy;';
if ( $build_year == $year ) {
    echo $year;
} else {
    echo $build_year . ' - ' . $year;	
}
echo ' ' . $blogname . '. All Rights Reserved.</p>' . PHP_EOL;
?>

<?php
//  As a ternary operator
    $build_year = '2018'; // Amend this accordingly using the YYYY format
    $current_year = date('Y'); // Get A full numeric representation of the current year, 4 digits
    $range = $build_year . '-' . $current_year;
?>
<p>&copy;<?php echo ( ( $build_year == $current_year ) ? $build_year : $range ) ?> Business Name. All Rights Reserved.</p>

<?php
// Returns either copyrighted date range or single date
function copyright( $build_year ) {
    // Build year should be in YYYY format
    $current_year = date('Y'); // Get A full numeric representation of the current year, 4 digits
    $blogname = get_bloginfo( 'name' ); // Get the Site Title as specified in Settings / General
    $copyright = '&copy;';
    if ( $build_year == $current_year ) {
        $copyright .= $current_year;
    } else {
        $copyright .= $build_year . ' - ' . $current_year;
    }
    $copyright .= ' ' . $blogname;
    return $copyright;
}
?>

Updated in early 2018, now available as a function.
Example usage:
<p><?php echo copyright( '2018' ) ?>. All Rights Reserved.</p>

Added a ternary operator version. Useful for templating.