Calculate working days between dates

getWorkingDays

$nr_work_days = getWorkingDays('2014-05-01','2014-05-06', null);
echo $nr_work_days;

/**
* Calculate the number of working days between two dates.
* Note: The result is inclusive of the start and end date. Given two adjacent weekday dates the result is 2
* Return 0 if the start date is greater than the end date
* @param  string $startDate           Starting date
* @param  string $endDate             End date
* @param  array  $additional_holidays Additional holidays to remove from the calculation
* @return int                      Number of working days
*/
function getWorkingDays($startDate, $endDate, $additional_holidays=array()){
	
	$bank_holidays = $holidays = array(
		'2014-04-18', // Good Friday
		'2014-04-21', // Easter Monday
		'2014-05-05', // Early May bank holiday
		'2014-05-26', // Spring bank holiday
		'2014-08-25', // Summer bank holiday
		'2014-12-25', // Christmas day
		'2014-12-26', // Boxing day

		'2015-01-01', // New Year's Day
		'2015-04-03', // Good Friday
		'2015-04-06', // Easter Monday
		'2015-05-04', // Early May bank holiday
		'2015-05-25', // Spring bank holiday
		'2015-08-31', // Summer bank holiday
		'2015-12-25', // Christmas day
		'2015-12-26', // Boxing day

		'2016-01-01', // New Year's Day
		'2016-03-25', // Good Friday
		'2016-03-28', // Easter Monday
		'2016-05-02', // Early May bank holiday
		'2016-05-30', // Spring bank holiday
		'2016-08-29', // Summer bank holiday
		'2016-12-25', // Christmas day
		'2016-12-26', // Boxing day

		'2017-01-01', // New Year's Day
		'2017-04-14', // Good Friday
		'2017-04-17', // Easter Monday
		'2017-05-01', // Early May bank holiday
		'2017-05-29', // Spring bank holiday
		'2017-08-28', // Summer bank holiday
		'2017-12-25', // Christmas day
		'2017-12-26', // Boxing day
	);

	if (count($additional_holidays)) {
		$holidays = array_merge($bank_holidays, $additional_holidays);
	}

	$begin=strtotime($startDate);
	$end=strtotime($endDate);
	
	if ($begin > $end) {  
		return 0;
	} else {
		$no_days=0;
		$weekends=0;

		while ($begin <= $end) {
			$no_days++; // no of days in the given interval
			$what_day = date("N", $begin);
			if ($what_day > 5) { // 6 and 7 are weekend days
				$weekends++;
			}
			$begin+=86400; // +1 day
		}

		$working_days = $no_days-$weekends;

		$begin=strtotime($startDate);
		$end=strtotime($endDate);

		//subtract holidays
		foreach($holidays as $holiday){
		    $time_stamp=strtotime($holiday);
		    //If the holiday doesn't fall in weekend
			if ($begin <= $time_stamp && $time_stamp <= $end && date("N",$time_stamp) != 6 && date("N",$time_stamp) != 7) {				
				$working_days--;
			}
		}


		return $working_days;
	}
}