Try this: using System; class Program { static void Main() { while(true) { Console.Write(Enter Employee name or 'Quit' to quit : ); string name = Console.ReadLine(); if (name == Quit) return; double hoursWorked; double hourlyRate; while(true) { Console.Write(Enter Hours Worked : ); bool isValid = Double.TryParse(Console.ReadLine() out hoursWorked); if (isValid) break; Console.WriteLine(Not a valid number. Please try again); } while(true) { Console.Write(Enter Hourly Rate of Pay : ); bool isValid = Double.TryParse(Console.ReadLine() out hourlyRate); if (isValid) break; Console.WriteLine(Not a valid number. Please try again); } Console.WriteLine(); double grossPay = CalculateGrossPay(hoursWorked hourlyRate); Console.WriteLine(Gross pay = {0:C} grossPay); double stateTax = CalculateStateTax(grossPay); Console.WriteLine(State tax = {0:C} stateTax); double federalTax = CalculateFederalTax(grossPay); Console.WriteLine(Federal tax = {0:C} federalTax); double FICATax = CalculateFICATax(grossPay); Console.WriteLine(FICA tax = {0:C} FICATax); double netPay = CalculateNetPay(grossPay stateTax federalTax FICATax); Console.WriteLine(Net pay = {0:C} netPay); Console.WriteLine(); } } static double CalculateGrossPay(double hoursWorked double hourlyRate) { return Math.Round(hoursWorked * hourlyRate 2); } static double CalculateStateTax(double grossPay) { return Math.Round(grossPay * 0.04 2); } static double CalculateFederalTax(double grossPay) { return Math.Round(grossPay * 0.23 2); } static double CalculateFICATax(double grossPay) { return Math.Round(grossPay * 0.14 2); } static double CalculateNetPay(double grossPay double stateTax double federalTax double FICAtax) { return Math.Round(grossPay - (stateTax + federalTax + FICAtax) 2); } }