function savings() {
var monthsub = calc.monthsub.value;
var freeminutes = calc.freeminutes.value;

var a = Math.floor(monthsub);
var b = Math.floor(calc.detailbill.value);
var c = Math.floor(calc.cli.value);
var d = Math.floor(freeminutes);

var e = (a+b+c);
var ccostpmin = (a+b+c)/d;
var sfactor = 1.5;
var cspend = sfactor*e;
var cminutes = cspend/ccostpmin;
var ysavings = (cspend - cminutes*0.1-89)*12;



calc.costpermin.value = Math.round(ccostpmin*100)/100;
calc.spend.value = Math.round(cspend*100)/100;
calc.savingpa.value = Math.round(ysavings*100)/100;

return false;
}