function calculate_loan() {
	var lc_loanamount = parseInt(document.getElementById('lc_loanamount').value);
	var lc_loanterm = parseInt(document.getElementById('lc_loanterm').value);
	var lc_interestrate = parseInt(document.getElementById('lc_interestrate').value);
	var lc_result = document.getElementById('lc_result');
	
	if (
		(isNaN(lc_loanamount) || isNaN(lc_loanterm) || isNaN(lc_interestrate)) ||
		(lc_loanamount == 0) || (lc_loanterm == 0) || (lc_interestrate == 0)
	) {
		lc_result.value = "No data";
	} else {
		//var princ = document.calc.loan.value;
		//var term  = document.calc.months.value;
		//var intr   = document.calc.rate.value / 1200;
		lc_interestrate = lc_interestrate / 1200;
		if (lc_loanterm < 8) lc_loanterm *= 12;
		
		lc_result.value = lc_loanamount * lc_interestrate / (1 - (Math.pow(1/(1 + lc_interestrate), lc_loanterm)));
	}
	
	// payment = principle * monthly interest/(1 - (1/(1+MonthlyInterest)*Months))
}