array averages please help

How can I find the overall averages of the columns in this array?

when i run my code it gives me an output that looks like this (showing me wrong averages):

0 1 2 3 overall grade

Badger,Bradley 37 70 51 48 68.66666666666667

Emu,Emma 35 81 75 40 72.83333333333334

Aardvark,Alice 42 85 22 0 65.11111111111111

Dodo,Donald exc 12 25 0 54.17391304347826

Cassowary,Cassie 50 97 72 68 62.758620689655174

my code is :

Java Code:

 public static double[] computeAllGrades(int[][] scoreTable, int[] itemPointValues)
        {
               
                 {
             double totalPoints = 0;
             double totalPointsPossible = 0;
             double allGrades[];
             double grade =0;
           
             allGrades= new double[scoreTable.length];
             int k = 0;
           
             for(int j = 0 ; j < scoreTable.length ; j++)
             {
                     for(int i = 0 ; i < scoreTable[0].length ; i++)
                     {
                             if(scoreTable[j][i] == -1)
                     {
                             totalPoints = totalPoints + 0;
                             totalPointsPossible = totalPointsPossible + 0;
                           
                     }
                     else
                     {
                             totalPoints = totalPoints + scoreTable[j][i];
                     totalPointsPossible = totalPointsPossible + itemPointValues[i];
                     }
                                     grade = (totalPoints/totalPointsPossible)*100;
                                   
                     }
                     
                     allGrades[k] = grade;
                     k++;
             }
           
           
             return allGrades;}}