Converting dataset into proper CSV notation for downloading using JavaScript

Utilizing partial advice given by @Heretic Monkey (for transposing the data) and @codeWonderland (for adding category names), I have arrived at the following solution:

// Reference to pulled-data arrays
let data = [
  this.set1
  this.set2
  this.set3
  this.set4
  this.set5
];

// NEW
// Reference to data array names in same order as aforementioned data array
const dataNames = [
  'set1',
  'set2',
  'set3',
  'set4',
  'set5',
]

// NEW
// Add label to each column
data.forEach((datum, index) => {
  datum.unshift(dataNames[index]);
});

// Convert data arrays to CSV format
const CSVURL = 'data:text/csv;charset=UTF-8,';
let transposedData = data[0].map((col, i) => data.map(row => row[i])); // NEW: TRANSPOSE DATA
let formattedData = transposedData.map(e => e.join(',')).join('\n'); // Modified
let encodedData = CSVURL + encodeURIComponent(formattedData);

// Generic download CSV function
downloadFile('name.csv', encodedData);

Also noting the recent addition for alternative column labeling by @Kosh Very , quoted as:

// pull arrays by headers
data[0].forEach(h => data.push(this[h]));