function calcFuel(){
//Calculate Fuel Reduction
var fuelGal = document.gps.fuel_gal.value;
var fuelCost = document.gps.fuel_cost.value;
var fuelTotal = fuelGal * fuelCost;

// rounds total to two decimal places
fuelTotal = "" + ((Math.round(fuelTotal * 100)) / 100);
var dec1 = fuelTotal.substring(fuelTotal.length-3, fuelTotal.length-2);
var dec2 = fuelTotal.substring(fuelTotal.length-2, fuelTotal.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') fuelTotal += "0";
else fuelTotal += ".00";
}
document.gps.fuel_total.value = fuelTotal;
}

function changeLook(){
var newFuelCost = document.gps.fuel_cost.value;
var newPayRate = document.gps.pay_rate.value;
var newSalesRate = document.gps.sales_rate.value;

// rounds total to two decimal places
newFuelCost = "" + ((Math.round(newFuelCost * 100)) / 100);
var dec1 = newFuelCost.substring(newFuelCost.length-3, newFuelCost.length-2);
var dec2 = newFuelCost.substring(newFuelCost.length-2, newFuelCost.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') newFuelCost += "0";
else newFuelCost += ".00";
}
document.gps.fuel_cost.value = newFuelCost;

// rounds total to two decimal places
newPayRate = "" + ((Math.round(newPayRate * 100)) / 100);
var dec1 = newPayRate.substring(newPayRate.length-3, newPayRate.length-2);
var dec2 = newPayRate.substring(newPayRate.length-2, newPayRate.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') newPayRate += "0";
else newPayRate += ".00";
}
document.gps.pay_rate.value = newPayRate;

// rounds total to two decimal places
newSalesRate = "" + ((Math.round(newSalesRate * 100)) / 100);
var dec1 = newSalesRate.substring(newSalesRate.length-3, newSalesRate.length-2);
var dec2 = newSalesRate.substring(newSalesRate.length-2, newSalesRate.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') newSalesRate += "0";
else newSalesRate += ".00";
}
document.gps.sales_rate.value = newSalesRate;
}

function calcPay(){
//Calculate Payroll Reduction
var payHours = document.gps.pay_hrs.value;
var payRate = document.gps.pay_rate.value;
var payTotal = payHours * payRate;

// rounds total to two decimal places
payTotal = "" + ((Math.round(payTotal * 100)) / 100);
var dec1 = payTotal.substring(payTotal.length-3, payTotal.length-2);
var dec2 = payTotal.substring(payTotal.length-2, payTotal.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') payTotal += "0";
else payTotal += ".00";
}
document.gps.pay_total.value = payTotal;
}

function calcSales(gps){
//Calculate Sales Increase
var salesRate = document.gps.sales_rate.value;
var salesCalls = document.gps.sales_calls.value;
var salesTotal = salesRate * salesCalls;

// rounds total to two decimal places
salesTotal = "" + ((Math.round(salesTotal * 100)) / 100);
var dec1 = salesTotal.substring(salesTotal.length-3, salesTotal.length-2);
var dec2 = salesTotal.substring(salesTotal.length-2, salesTotal.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') salesTotal += "0";
else salesTotal += ".00";
}
document.gps.sales_total.value = salesTotal;
}

function calcWKSales(gps){
//Totals up Total weekly sales
var fuelTotal = document.gps.fuel_total.value;
var payTotal = document.gps.pay_total.value;
var salesTotal = document.gps.sales_total.value;
var weekTotal = (Math.round(fuelTotal*100)/100) + (Math.round(payTotal*100)/100) + (Math.round(salesTotal*100)/100);

// rounds total to two decimal places
weekTotal = "" + ((Math.round(weekTotal * 100)) / 100);
var dec1 = weekTotal.substring(weekTotal.length-3, weekTotal.length-2);
var dec2 = weekTotal.substring(weekTotal.length-2, weekTotal.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') weekTotal += "0";
else weekTotal += ".00";
}
document.gps.save_week.value = weekTotal;
}

function calcMonSavings(){
//Totals up Monthly Savings
var saveMonth = Math.round((Math.round(document.gps.save_week.value*1000)/1000*52/12)*100)/100;

// rounds total to two decimal places
saveMonth = "" + ((Math.round(saveMonth * 100)) / 100);
var dec1 = saveMonth.substring(saveMonth.length-3, saveMonth.length-2);
var dec2 = saveMonth.substring(saveMonth.length-2, saveMonth.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') saveMonth += "0";
else saveMonth += ".00";
}
document.gps.save_month.value = saveMonth;
}

function calcNetSavings(){
//Totals up Net Savings
var netSavings = (Math.round(document.gps.save_month.value*1000)/1000) - (Math.round(document.gps.save_service.value*1000)/1000);

// rounds total to two decimal places
netSavings = "" + ((Math.round(netSavings * 100)) / 100);
var dec1 = netSavings.substring(netSavings.length-3, netSavings.length-2);
var dec2 = netSavings.substring(netSavings.length-2, netSavings.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') netSavings += "0";
else netSavings += ".00";
}
document.gps.net_save.value = netSavings;
}

function calcNetVeh(){
//Totals up Monthly Savings times the number of trucks in fleet
var netTotal = (Math.round(document.gps.net_save.value*1000)/1000) * (Math.round(document.gps.net_veh.value*1000)/1000);

// rounds total to two decimal places
netTotal = "" + ((Math.round(netTotal * 100)) / 100);
var dec1 = netTotal.substring(netTotal.length-3, netTotal.length-2);
var dec2 = netTotal.substring(netTotal.length-2, netTotal.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') netTotal += "0";
else netTotal += ".00";
}
document.gps.net_total.value = netTotal
}

function calcAnnSav(){
//Totals up the Total Annual Savings
var annualTotal = Math.round((Math.round(document.gps.net_total.value*1000)/1000 * 12)*100)/100;

// rounds total to two decimal places
annualTotal = "" + ((Math.round(annualTotal * 100)) / 100);
var dec1 = annualTotal.substring(annualTotal.length-3, annualTotal.length-2);
var dec2 = annualTotal.substring(annualTotal.length-2, annualTotal.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') annualTotal += "0";
else annualTotal += ".00";
}
document.gps.annual_total.value = annualTotal;
}

function calcBeVeh(){
//Multiplies number of vehicles times Initial costs
var beVeh = (Math.round(document.gps.net_veh.value*1000)/1000) * (Math.round(document.gps.be_costs.value*1000)/1000);

// rounds total to two decimal places
beVeh = "" + ((Math.round(beVeh * 100)) / 100);
var dec1 = beVeh.substring(beVeh.length-3, beVeh.length-2);
var dec2 = beVeh.substring(beVeh.length-2, beVeh.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') beVeh += "0";
else beVeh += ".00";
}
document.gps.be_veh.value = beVeh
}

function calcBeMonths(){
//Determines number of months to breakeven
beMonths = (Math.round(document.gps.be_costs.value*1000)/1000) / (Math.round(document.gps.net_save.value*1000)/1000);

// rounds total to two decimal places
beMonths = "" + ((Math.round(beMonths * 100)) / 100);
var dec1 = beMonths.substring(beMonths.length-3, beMonths.length-2);
var dec2 = beMonths.substring(beMonths.length-2, beMonths.length-1);
// adds trailing zeroes if necessary
if (dec1 != '.') {
if (dec2 == '.') beMonths += "0";
else beMonths += ".00";
}
document.gps.be_months.value = beMonths
}