Generate random number between 0.0 to 10000.0 in c#

I'm using c# to generate 1000 random number between 0.0 to 10000.0. The output need to be two decimal places , and be dispaly as following

1   18.92
2   874.32
3   7182.56
4   90.54
5   254.17
6   689.78

Here is my code :

using (var writer = new StreamWriter("d:\\data.txt"))
        {
            Random random = new Random();
            float randomNumber = random.Next(0, 10001);
            string rndnumber = randomNumber.ToString("0.00");
            for (int i = 1; i<= 1000; i++)
            {
                for (int count = 1; count <= 1000; count++)
                {
                    writer.Write("{0},\n {0:0.0}", count, rndnumber);
                }
            }

But so far my output look like this:

1, 1.02, 2.03, 3.04, 4.05, 5.06, 6.07, 7.08, 8.09, 9.010, 10.011, 11.012

What did I missing?