Тrain the trainers

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Train_The_Trainers
{
    class Program
    {
        static void Main(string[] args)
        {
            int people = int.Parse(Console.ReadLine());
            double score = 0;
            double counter = 0;

            while (true)
            {
                string presentation = Console.ReadLine();
                double sumOfGrades = 0;

                if (presentation == "Finish")
                {
                    double scoreSum = score / counter;
                    Console.WriteLine($"Student's final assessment is {scoreSum:f2}.");
                    break;
                }
                for (int i = 0; i < people; i++)
                {
                    double grade = double.Parse(Console.ReadLine());
                    sumOfGrades += grade;
                    score += grade;
                    counter++;
                }
                double sumAfter = sumOfGrades / people;
                Console.WriteLine($"{presentation} - {sumAfter:f2}.");

            }
        }
    }
}