Como inserir o código de rastreamento do Google Analytics no theme?

<!DOCTYPE html>
<?php $options = get_option('minimalia'); ?>
<html class="no-js" <?php language_attributes(); ?>>
<head>
<meta name="google-site-verification" content="12Rf1IrgIFxup3hdpILZx5V38KFmzzmF26VMTryPUAs" />
	<meta charset="<?php bloginfo('charset'); ?>">
	<title><?php wp_title(''); ?></title>
	<?php mts_meta(); ?>
	<link rel="stylesheet" type="text/css" media="all" href="<?php bloginfo( 'stylesheet_url' ); ?>" />
	<link rel="pingback" href="<?php bloginfo( 'pingback_url' ); ?>" />
	<?php wp_enqueue_script("jquery"); ?>
	<?php if ( is_singular() ) wp_enqueue_script( 'comment-reply' ); ?>
	<!--[if lt IE 9]>
	<script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
	<![endif]-->
	<?php wp_head(); ?>
	<?php mts_head(); ?>
</head>

<script>
  (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
  (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
  m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
  })(window,document,'script','//www.google-analytics.com/analytics.js','ga');

  ga('create', 'UA-20306233-1', 'auto');
  ga('send', 'pageview');

</script>