add_action( 'amp_post_template_head', 'amp_post_template_add_analytics_js' );
function amp_post_template_add_analytics_js( $amp_template ) {
	$post_id = $amp_template->get( 'post_id' );
	?>
	<script async custom-element="amp-analytics" src="https://cdn.ampproject.org/v0/amp-analytics-0.1.js"></script>
	<?php
}

add_action( 'amp_post_template_footer', 'xyz_amp_add_analytics' );

function xyz_amp_add_analytics( $amp_template ) {
    $post_id = $amp_template->get( 'post_id' );
    ?>
	<amp-analytics type="googleanalytics" id="analytics1">
	<script type="application/json">
	{
	  "vars": {
		"account": "UA-XXXXX-Y"
	  },
	  "triggers": {
		"trackPageview": {
		  "on": "visible",
		  "request": "pageview"
		}
	  }
	}
	</script>
	</amp-analytics>
    <?php
}