The data comes the Metacritic user ratings of 100 popular TV shows: all of which have a minimum of three seasons. Metacritic user ratings work on a 1-10 scale, with ratings that are specific for every season. For example, Breaking Bad’s fifth season holds a 9.7, whereas the fourth season of Heroes has a 3.3.

Out of the 100 shows used, 11 of them had over 10 seasons. The longest show was The Simpsons with 28 rated seasons. The average show had 6.7 seasons.

On average, the best season of a show was season 2.29 (the most common best season was the first one). The worst season was season 5.4 (the most common worst season was 4).

The reason season 8 has such a low score is because the eighth season of Shameless (US) has a 0.8 rating. However, even without that rating, season 8 would still have the lowest score. Usually season 8 is going to pretty bad.