It was already renewed for a 10th season earlier this year. Anything beyond that is uncertain at this time.
The show has definitely gone downhill, but that was inevitable. It is extremely rare for a long-lasting show to retain the same level of excellence during its entire duration. It's safe to say that we'll never again see a season as constantly strong and original as the first five seasons, and to be honest, for the show to have been as good as it was during those first five seasons is quite the feat given the limited premise.
Thanks for the information. About to watch the season finale