// Jake Holmesby, 22nd March 2012

            double dFuelPrice, dFuelCost, dCurrentOdo, dPreviousOdo, dFuelAmount, dOdoTotal, dLitresKilometres, dFuelGallons, dOdoMiles, dMilesGallons;
            int iFuelBar;
            dFuelPrice = Convert.ToDouble(FuelPriceTxtbx.Text);
            dFuelCost = Convert.ToDouble(FuelCostTxtbx.Text);
            dCurrentOdo = Convert.ToDouble(CurrentOdoTxtbx.Text);
            dPreviousOdo = Convert.ToDouble(PreviousOdoTxtbx.Text);

            // Litres per 100 km conversion calculation

            dFuelAmount = dFuelCost / dFuelPrice * 100;
            dOdoTotal = dCurrentOdo - dPreviousOdo;
            dLitresKilometres = dFuelAmount / dOdoTotal * 100;
            ConsumptionKmLbl.Text = "Consumption is " + Convert.ToString(dLitresKilometres) + " l/100km";

            // Miles per Gallon conversion calculation

            dFuelGallons = dFuelAmount * 4.546;
            dOdoMiles = dOdoTotal * 1.609;
            dMilesGallons = dOdoMiles / dFuelGallons;
            ConsumptionMilesLbl.Text = "or " + Convert.ToString(dMilesGallons) + " mpg";

            // Fuel Consumption Bar

            Graphics fuelbar = ConsumptionPicbx.CreateGraphics();
            SolidBrush brshBlack = new SolidBrush(Color.Black);
            iFuelBar = Convert.ToInt32(dLitresKilometres / 24 * 240);
            fuelbar.FillRectangle(brshBlack, iFuelBar, 0, 5, 44);