Any honest, self-respecting fan of The Simpsons will tell you that the show just isn’t what it used to be.

If you believe that the series has had a gradual decline in the quality of its output since it debuted in 1989, then British producer and 'Diminishing Returns' podcaster Sol Harris agrees with you.

Sol, who must have a very understanding boss/partner, has just spent the three to four months watching all 28 seasons of the show noting the highs, lows and everything in-between.

He rated each episode out of ten and then gave each season an average overall mark. Using that data he plotted out a ‘The Decline of The Simpsons’ chart complete with some episode names and notes and posted it on Twitter.

Seasons three to eight are highlighted as ‘The Golden Years’ while season 6, which has episodes like ‘Bart vs. Australia’ and ‘Who Shot Mr. Burns?’, is pinpointed as the best.

He also marks out an episode on November 11th 2011 as "the definitive moment when the show went from 'bad Simpsons' to 'bad television.” Ouch.

We think Sol’s chart is pretty much on the money. What do you think?