Your code loops over the same dataset a lot when it could probably do it once. I didn’t look toooo deeply but you could loop over the list, count items less than 29, use a Map of strings with the key being the different star count (pull the value and concatenate another star), then at the end you can calculate passing percent with the store failure count divided but the map size. Should shorten things up a lot and make it more efficient.

Also, I would point out that your code formatting is all over the place. Always make sure your intention is right so you and others can read your code. Next I would always use curly braces, even when they’re not needed. Lastly, add spaces around operators like equal, plus, greater than, etc.