php-percentage-calc-format.php

<?php

function employeeGrowth ( int $employees, int $employees_6_months_ago) {

	$employee_percent_change = ($employees - $employees_6_months_ago)/$employees_6_months_ago;
	
	$formatter = new NumberFormatter('en_US', NumberFormatter::PERCENT);
	
	echo $formatter->format($employee_percent_change);

}

$employees = 26258;
$employees_6_months_ago = 21011;

employeeGrowth($employees,$employees_6_months_ago);