You can parse the YEAR from both the MIN and MAX dates of a contract group belonging to the desired company. I would likely use a script to do this, triggered manually or automatically based on need.
Depending on the overall use case, there's a few options to render the info into a report or store it within the contract record as an array of start dates and most recent dates. (separate fields, or one, depending on your level of need. Example: "2016|companName|2022, 2018|companyName2|2024".
Le would be glad to help, if needed.
shawnjp@gmail.com
-Shawn
慄Time Wizard