Populating a cell with a string in a datagrid view based on if statement

I have a datagridview which displays values in an array. I would like the 5th column to show a string based on the data in the previous columns. I have a foreach loop as you can see but column 5 is still appearing blank. All help appreciated.

        try
        {
            if (File.Exists("competitorDetailsFile.txt")) //if this 
file exists
            {
                string[] detailsArray = 
File.ReadLines("competitorDetailsFile.txt").ToArray(); //write data to 
array
                double time = 0;
                double time1 = 0;




                for (int number = 0; number < detailsArray.Length; 
number++)
                {
                    string[] detailsArray2 = 
detailsArray[number].Split('~'); //split on tilda

                    time1 = Convert.ToDouble(detailsArray2[3]) + 
Convert.ToDouble(detailsArray2[4]) + Convert.ToDouble(detailsArray2[5]) 
+ Convert.ToDouble(detailsArray2[6]) + 
Convert.ToDouble(detailsArray2[7]);
                    time = time1 / 5;
                    int score = Convert.ToInt32(detailsArray2[8]);




                    //time is equal to the average of the ski times 
                    dataGridView1.Rows.Add(detailsArray2[0], 
Convert.ToDouble(detailsArray2[1]), Convert.ToInt32(detailsArray2[8]), 
time);

                    {
                        foreach (DataGridViewRow row in 
dataGridView1.Rows)
                        {
                            foreach (DataGridViewCell cell in 
row.Cells)
                            {
                                if (time > 100)
                                {
                                    row.Cells[5].Value = "LOW";
                                }
                                else if (time < 100)
                                {
                                    row.Cells[5].Value = "HIGH";
                                }

                            }
                        }
                    }