Как использовать событие onkeyup несколько раз в одном поле ввода в jQuery?

Я работаю над формой, в которой хочу произвести расчеты. Я использую для этого jquery. Ниже приведен html-код и функция jquery для того же.

function sum(param,id) 
        {
            var daysWork = document.getElementById('days_work_'+id).value;
            var rateReceived = document.getElementById('rateReceived_'+id).value;
            var percPaid = document.getElementById('perc_paid_'+id).value;
            var paidFrmUk = document.getElementById('paidFrmUk_'+id).value;
            var paidFrmIndia =  document.getElementById('paid_from_india_'+id).value;
            var remaining =  document.getElementById('remaining_'+id).value;


            var totalDisplay = rateReceived * daysWork;
            var total = totalDisplay.toFixed(2);
            document.getElementById('total_'+id).value = total;   

            var toBePaidDisplay = (totalDisplay * percPaid)/100;
            var toBePaid = toBePaidDisplay.toFixed(2);
            document.getElementById('tobe_paid_'+id).value = toBePaid;

            var paidFrmIndiaDisplay = toBePaid - paidFrmUk;
            var paidFrmIndia = paidFrmIndiaDisplay.toFixed(2);
            var paidFrmIndia = document.getElementById('paid_from_india_'+id).value = paidFrmIndia;

            var addUkIndiaSal = Number(paidFrmIndia) + Number(paidFrmUk);
            var remainingDisplay = toBePaid - addUkIndiaSal;    
            var remaining = remainingDisplay.toFixed(2);
            document.getElementById('remaining_'+id).value = remaining;

        }



<td><?php echo $RATE_RECEIVED;?></td>
<td><?php echo $CURRENCY_CODE;?></td>   
<td><?php echo $PERC_PAID;?></td>    
<td><input type = "text" onkeyup = "sum(this,<?php echo $srNo;?>)"   id = "days_work_<?php echo $srNo;?>"  value = "<?php echo $DAYS_WORKED;?>" /></td> 
<td><input type = "text"  id = "total_<?php echo $srNo;?>"  value = "<?php echo $TOTAL;?>"  /></td> 
    <td align = "center"><input type = "text"    id = "tobe_paid_<?php echo $srNo;?>"  value = "<?php echo $PER_TO_BE_PAID; ?>"  /></td> 
<td><input type = "text" onkeyup = "sum(this,<?php echo $srNo;?>)"  id = "paidFrmUk_<?php echo $srNo;?>"  value = "<?php echo$SAL_PAY_FRM_UK;?>" /></td>            
<td><input type = "text" onkeyup = "sum(this,<?php echo $srNo;?>)"  id = "paid_from_india_<?php echo $srNo;?>"  value = "<?php echo $SAL_PAY_FRM_INDIA;?>"  /></td> 
<td><input type = "text" onkeyup = "sum(this,<?php echo $srNo;?>)"   id = "remaining_<?php echo $srNo;?>"  value = "<?php echo$REMAINING;?>"  /></td>

Мой код работает нормально в соответствии с моей функцией. но у меня есть другие условия, которые я не могу выполнить с помощью этого кода.

Как вы можете видеть последние 3 входа в td paidFrmUk_, paid_from_india_, слева_. Мой расчет похож на payFrmIndia = = toBePaid - payFrmUk;

its working. but if i want to edit paidFrmUk after calculation it wont allow me to edit that input box. what is the solution for this. to edit input box once calculated by function.