This gist is to loop the posts in a specific year in a chunk by year.

loop posts by year

//create two custom functions
<?php //retrive years that have posts
function st_get_years_having_posts( $post_type ) {
	// get years that have posts
	global $wpdb;
	$date_query = "SELECT YEAR(post_date) AS year FROM {$wpdb->prefix}posts WHERE post_type = '{$post_type}' AND post_status = 'publish' GROUP BY year DESC";
	$years = $wpdb->get_results( $date_query  );
	return $years;
}

// get post data by year
function st_posts_this_year( $post_type, $year ){
	global $wpdb;
	$press_query = "SELECT * FROM {$wpdb->prefix}posts WHERE post_type = '{$post_type}' AND post_status = 'publish' AND YEAR(post_date) = '" . $year . "'" ;
	// get posts for each year
	$posts_this_year = $wpdb->get_results( $press_query );
	return $posts_this_year;
}?>
//implement like this
<?php $years = st_get_years_having_posts('press'); //st_get_years_having_posts($post_type);
                foreach ( $years as $year ) {
                    $year = $year->year;
                    $posts_this_year = st_posts_this_year( 'press', $year );?>