Use the reduce Method to Analyze Data_One line solution

I came up with this one line solution

function getRating(watchList){
  var averageRating=watchList
  .filter(a=>a.Director=="Christopher Nolan")
  .reduce((a,x,i)=>
  (Number(x.imdbRating)+i*a)/(1+i)
  ,0);
  return averageRating;
}

Challenge: Use the reduce Method to Analyze Data

Link to the challenge:

It is great that you solved the challenge, but instead of posting your full working solution, it is best to stay focused on answering other poster’s question(s) and help guide them with hints and suggestions to solve their own issues with the challenge.

We are trying to cut back on the number of spoiler solutions found on the forum and instead focus on helping other campers with their questions and definitely not posting full working solutions.

Thank you for understanding.

Hi Dan!
I am new here.
I thought this solution could be useful as all the solutions available are long. So I wanted to share this simple solution so that it can help anyone.
But thank you for the explanation.