I have spent some time entering Containers into the N-Scale database. What a complicated field!
The number of companies and the mergers have made it quite a challenge in finding out Company information.
Here is a graphic of mergers and consolidations for 1990s to 2007
Hope this helps.
About the Author
I collect North American engines and freight with a focus on Canadian railroads along with some northern U.S. lines and all their predecessors. I became re-interested in model RRing when DCC was introduced and have been using DCC since the early 90s. As a member (since 2017) and a curator at TroveStar, I regularly contribute to the TroveStar N Scale Model Trains Database (data and blogs).