Football Outsiders went back 30 years to find the best offenses in the NFL (ESPN Insider subscription required). Cracking the list at #29 was the 2000 St. Louis Rams (the season after winning Super Bowl XXXIV and the season before the loss in Super Bowl XXXVI):

29. 2000 St. Louis Rams +24.5 percent The 2000 Rams couldn't follow up on their Super Bowl title because the defense collapsed, ranking 27th in DVOA that season. However, 2000 was the best year for the "Greatest Show on Turf" offense, even though Kurt Warner got injured and was replaced by Trent Green for five games. The Rams set the all-time NFL record by averaging 6.98 yards per play; no other team since 1960 has been over 6.7. The 2000 Rams also set an all-time record for highest team rushing DVOA (+36.5 percent).

Right in the middle of the “Greatest Show on Turf” era in St. Louis, the Rams were dominant on offense behind Kurt Warner/Trent Green (Warner was hurt for five games), Marshall Faulk, and a dynamic wide receiver group of Isaac Bruce and Torry Holt.

Sadly, the Rams’ offense has been nowhere close to the dominant level of the GSOT days. In a pullout in the story, they also list the top 5 worst offenses of the last 30 years, and the Rams make that list as well:

4. 2016 Los Angeles Rams -37.8 percent Jared Goff had the fifth-worst season by a quarterback in our database even though he started for just half the season.

The Rams actually regressed as an offensive unit the last three years. Somehow, after finishing 32nd in the league for yards under Jeff Fisher’s tutelage in 2015, the Rams were even worse in 2016.

With the new staff in tow, let’s hope the Rams will end up closer to the GSOT than the SOSAR.

(UPDATED at 8:34pm ET)

Got some good info from FO on Twitter that I thought was worth adding in:

The issue DVOA has with underrating the Rams and 98 Vikings is explained in the article. It's a bit of a fluke in the system. — Football Outsiders (@fboutsiders) June 19, 2017

DVOA is properly downgrading these teams for domes/easy sched, but also has trouble with their abnormal consistency on explosive plays. — Football Outsiders (@fboutsiders) June 19, 2017