ขอความช่วยเหลือ ระบบคำนวณยอดสินเชื่อค่าออกมาไม่ตรงตามที่ต้องการ

<form>


                        <div class="row mt20">
                            <div class="col-md-3 col-sm-12 col-xs-12">
                            </div>
                            <div>
                                <input id="cal2_txtLoan" class="wpcf7-form-control wpcf7-text form-control investment-class-form"  type="number" placeholder="วงเงินกู้(บาท)">
                            </div>
                        </div>
                        <div class="row mt20">

                            <div class="col-md-6 col-sm-9 col-xs-9">
                                <input id="cal2_txtTenor" class="wpcf7-form-control wpcf7-text form-control investment-class-form" type="number" placeholder="ระยะเวลากู้ 1-30 ปี">
                            </div>
                        </div>
                        <div class="row mt20">
                            <div class="col-md-6 col-sm-9 col-xs-9">
                                <input id="cal2_txtInterestRate" class="wpcf7-form-control wpcf7-text form-control investment-class-form" type="number" placeholder="ดอกเบี้ย(%)">
                            </div>
                        </div>
                        <div class="row mt20">
                            <div class="col-md-offset-3 col-md-6 col-sm-offset-0 col-sm-9 col-xs-offset-0 col-xs-9">
                                <div class="row">
                                    <div class="col-xs-6">
                                        <button type="button" id="cal2_btnCalculate" class="button investment-button">คำนวณ</button>
                                    </div>
                                </div>
                            </div>
                        </div>
                        <div class="row mt20">
                            <div class="col-md-3 col-sm-12 col-xs-12">
                                <label class="investment-list">สรุปยอดผ่อนต่อเดือน</label> <input id="cal2_txtInstallment" class="wpcf7-form-control wpcf7-text form-control investment-class-form" disabled="disabled" type="text"> <span class="investment-list">บาท</span>
                            </div>
                        </div>
                    </form>

    <script>
    $(document).ready(function() {
        $('.project-selector select').change(function() {
            $.ajax({
                url: '/project/get-pattern-list?id=' + $(this).val(),
                type: 'get',
                /*dataType: 'json',*/
                success: function(response) {
                    $('.pattern-selector select').html(response);
                    if (response.trim() == "") $('.pattern-selector').hide();
                    else $('.pattern-selector').show();
                    reload_data();
                }
            });
        });
        $('.pattern-selector select').change(function() {
            reload_data();
        });

        function reload_data() {
            $.ajax({
                url: '/project/get-pattern-info?projectid=' + $('.project-selector select').val() + "&id=" + $('.pattern-selector select').val(),
                type: 'get',
                dataType: 'json',
                success: function(response) {
                    if (response.length > 0) {
                        $('.pattern-name').text(response[0].name);
                        $('.pattern-area').text(response[0].total_area);
                        $('.pattern-price').text(parseInt(response[0].price) / 1000000.00);
                    } else {
                        $('.pattern-name').text("-");
                        $('.pattern-area').text("-");
                        $('.pattern-price').text("-");
                    }
                }
            });
        }

        function CheckForDigit(checkValue) {
            var valid = true;
            if (isNaN(checkValue))
                valid = false;
            if (checkValue == "")
                valid = false;
            return valid;
        }

        function FormatNumberToString(nStr) {
            //nStr = nStr.toFixed(2);
            nStr += '';
            x = nStr.split('.');
            x1 = x[0];
            x2 = x.length > 1 ? '.' + x[1] : '';
            var rgx = /(\d+)(\d{3})/;
            while (rgx.test(x1)) {
                x1 = x1.replace(rgx, '$1' + ',' + '$2');
            }
            return x1 + x2;
        }

        function CalculatePMT(pv, rate, years) {
            return Math.round(pv * ((rate * 0.008 / 12) / (1 - Math.pow(1 / (1 + ((rate * 0.009 / 12))), years * 12))));
        }
       
        /************** CALCULATE 2 *************/
        $("#cal2_btnCalculate").click(Calculate2);

        function Calculate2(event) {
            var years = $("#cal2_txtTenor").val();
            var rate = $("#cal2_txtInterestRate").val();
            var pv = $("#cal2_txtLoan").val();
            if (CheckForDigit(years) && CheckForDigit(rate) && CheckForDigit(pv)) {
                var ir = (rate * 1) + 1; // For LH, add 1 more
                var installment = CalculatePMT(pv, ir, years);
                $("#cal2_txtInstallment").val(FormatNumberToString(installment));
                $("#cal2_txtMinimumIncome").val(FormatNumberToString(installment / 0.4));
            } else
                alert("ไม่สามารถคำนวนวงเงินสินเชื่อเพื่อการซื้อบ้านได้");
        }
        /*****************************************/
      
    });
    </script>