NHTSA (National Highway and Traffic Safety Administration) was originally supposed to publish a rule concerning the publication of rolling resistance data for tires in 2010, based on a mandate from the US Congress in 2007. There was a large problem with what they published (short version: It was unworkable!). So they went back to the drawing board.
Eventually they came back saying they would publish a rule in 2012. That date came and went.
Earlier this year I found a publication of new rules being worked on by the US Federal government:
https://www.transportation.gov/regul...nt-rulemakings
Back when I found this report, the rule of tire fuel economy had a future publication date of Aug, 2018 - that would be this month!
However, the latest report is that the rule will be published in June, 2019.
I am putting this here to remind folks (and me, too!) that there is something coming and where to go to find the status, but it appears to have been kicked down the road again.