function doCalculation() {    var B3 = document.getElementById("B3").value;   var B4 = document.getElementById("B4").value;   var B5 = document.getElementById("B5").value;   var B6 = document.getElementById("B6").value;   var B7 = document.getElementById("B7").value;      var B8 = ((B4/(B3/4.546))*B5/100)-((B4/(B3*0.95/4.546))*B6/100);   var B9 = B7/(B8/12);      document.getElementById("B8").value = B8.toFixed(2);   document.getElementById("B9").value = B9.toFixed(0);    }