As of January 1, 2022 this chart will replace the “inter-company settlement agreement” chart, which adjusters used to simply call “the chart”. One of the problems with the old system is that it only applied to signatory insurance companies. There were a couple insurers that were not part of it (Kingsway comes to mind from the way, way back), and of course it did not apply to those without collision coverage.
Some of the fault attributions have changed.
The biggest one which jumps out to me is the chain collision. Under the old chart the sandwiched middle car would get the short end of the stick. The offending lead car (car C) would be responsible for 100% for the rear end damage to vehicle B, and C would be responsible for only 50% of the front end damage to vehicle B. This would leave vehicle B responsible for 50% of its own front end damage AND 100% of the rear end damage to vehicle A.
As of January 1, as long as the lead car caused the entire chain reaction, that lead car C will be fully liable for all the damage to vehicle B and vehicle A. See image below: