Find 20 business days prior to today's date c#, C#

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//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;

namespace Rextester
{
    
    public class Program
    {
        private static string Calculate(DateTime today)
        {
            DateTime currentDate = today;   
            int iday = 1;
            for (int i = 1; i < 11; i++)
            {
                if ((int)currentDate.DayOfWeek >= 6 || (int)currentDate.DayOfWeek == 0){
                    
                    //currentDate = currentDate.AddDays(-1);
                    
                }else
                {
                    iday = iday + 1;
                }
                currentDate = currentDate.AddDays(1);
                Console.WriteLine(currentDate.DayOfWeek);
                Console.WriteLine(iday);
               
            }
                 return currentDate.ToShortDateString();
        }
        
        public static void Main(string[] args)
        {
            //Your code goes here
            Console.WriteLine(Calculate(DateTime.Today));
        }
    }
}

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