function netIncome(form)
        {
        var totalWorth= 0;
        var totalDebt= 0;
        var MAX=10000000;       // 10 million

        for(j=0; j< document.forms[form].elements.length; ++j)
                {
                // Make sure we reset the totals fields (worth, debt, net) to 0 before proceeding with our sums.
                // If we don't we may end up adding in a value from a previous calculation
                if (document.forms[form].elements[j].name== "worth")
                        document.forms[form].elements[j].value=0;
                if (document.forms[form].elements[j].name== "debt")
                        document.forms[form].elements[j].value=0;
                if (document.forms[form].elements[j].name== "net")
                        document.forms[form].elements[j].value=0;

                // Only consider those input fields that were of type text. (i.e. ignore input buttons)
                if (document.forms[form].elements[j].type== "text")
                        {
                        worthPattern= /asset+/;
                        debtPattern= /expense+/;

                        if (worthPattern.test(document.forms[form].elements[j].name)== true)
                                {
                                checkNumeric(document.forms[form].elements[j], MAX);
                                //alert(document.forms[form].elements[j].value);
                                totalWorth+= parseFloat(document.forms[form].elements[j].value);
                                }

                        else if (debtPattern.test(document.forms[form].elements[j].name)== true)
                                {
                                checkNumeric(document.forms[form].elements[j], MAX);
                                totalDebt+= parseFloat(document.forms[form].elements[j].value);
                                }
                        }

                }

        // Assign the total value calculations back to the "worth", "debt", & "net" fields in the form
        document.income.worth.value= totalWorth;
        document.income.debt.value= totalDebt;
        document.income.net.value= parseFloat(totalWorth)- parseFloat(totalDebt);
        }