Duplicates in JS Array

duplicates2.js

const data = [
  { name: "Dev User", department: "ICT", taskPercentCompleted: 100 },
  { name: "John Doe", department: "Finance", taskPercentCompleted: 100 },
  { name: "Jane Doe", department: "Human Resource", taskPercentCompleted: 10 },
  { name: "Jane Doe", department: "Human Resource", taskPercentCompleted: 100 },
  { name: "Dev User", department: "ICT", taskPercentCompleted: 90 },
  { name: "John Doe", department: "ICT", taskPercentCompleted: 100 },
  { name: "John Doe", department: "ICT", taskPercentCompleted: 100 },
];

function countDuplicates(originalArray) {
  var compressedArrayData = [];
  const arrayCopy = originalArray.slice(0);

  for (var i = 0; i < originalArray.length; i++) {
    var counter = 0;
    var avg = 0;
    for (var j = 0; j < arrayCopy.length; j++) {
      if (originalArray[i]["name"] === arrayCopy[j]["name"]) {
        avg += arrayCopy[j]["taskPercentCompleted"];
        counter++;
      }
    }

    if (counter > 0) {
      var revisedFormat = new Object();
      revisedFormat.name = originalArray[i]["name"];
      revisedFormat.department = originalArray[i]["department"];
      revisedFormat.taskPercentCompleted =
        originalArray[i]["taskPercentCompleted"];
      revisedFormat.avg = avg / counter;
      revisedFormat.count = counter;
      compressedArrayData.push(revisedFormat);
    }
  }

  return compressedArrayData;
}

const validatedValues = countDuplicates(data);
console.log(data);

console.log(validatedValues);

//Get unique pairs
//Here i have used name to filter

let uniqueAssignment = validatedValues.filter(
  (uniqueAssignment, index, self) =>
    index ===
    self.findIndex(
      (t) =>
        t.name === uniqueAssignment.name && t.name === uniqueAssignment.name
    )
);
console.log(uniqueAssignment);