I'm trying to display a post that was the most popular a year ago on the day it was posted. So today would be October 12, 2019.

I would like to base it off of this:

functions.php:

function setPostViews($postID) {
    $countKey = 'post_views_count';
    $count = get_post_meta($postID, $countKey, true);
    if($count==''){
        $count = 0;
        delete_post_meta($postID, $countKey);
        add_post_meta($postID, $countKey, '0');
    }else{
        $count++;
        update_post_meta($postID, $countKey, $count);
    }
}

loop template:

setPostViews(get_the_ID());
<?php
query_posts('meta_key=post_views_count&orderby=meta_value_num&order=DESC');
if (have_posts()) : while (have_posts()) : the_post();
?>
    <li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
<?php
endwhile; endif;
wp_reset_query();
?>