<?php

$count = 1;
$date_array = array();
while ($count <= 12) {
	
	// Calculate date
	$query_year = date('Y', strtotime('-' . $count . ' months America/Chicago'));
	$query_month = date('m', strtotime('-' . $count . ' months America/Chicago'));
	$display_month = date('M', strtotime('-' . $count . ' months America/Chicago'));
	
	$date_array[] = array(
		'query_year' => $query_year,
		'query_month' => $query_month,
		'display_month' => $display_month
	);

	$count ++;
	
}

print_r($date_array);