Function with reference and value type parameter

class Program
{
static int age = 30;
static void Main(string[] args)
 	 {
 	 // Value Type
	  Console.WriteLine("Your birth year is {0}", ValBirthYear(age));
          Console.WriteLine("if your age is {0}", age);
   	  // Reference Type
 	  Console.WriteLine("Your birth year is {0}", RefBirthYear(ref age));
 	  Console.WriteLine("if your age is {0}", age);
 	  Console.ReadKey();
  }
     //Function with value type parameter
      private static string ValBirthYear( int Vage)
        {
            int year = DateTime.Now.Year - Vage; 
            Vage = year; //Assigning the calculated value to the parameter
            return Convert.ToString(year);
        }
     //Function with reference type parameter. Notice the use of ref keyword.
      private static string RefBirthYear(ref int Rage)
        {
            int year = DateTime.Now.Year - Rage; 
            Rage = year;   //Assigning the calculated value to the parameter
            return Convert.ToString(Rage);
       }
    }

Output (Value Type)
Your birth year is 1980
If your age is 30
Output (Ref Type)
Your birth year is 1980
If your age is 1980