<?php
$tests = array(131.505, 131.515, 131.525, 131.535, 131.545, 131.555, 131.565, 131.575, 131.585, 131.595);
foreach($tests as $n) {
	echo $n, " => ", round($n, 2, PHP_ROUND_HALF_EVEN), PHP_EOL;
}