A snapshot of all messages in the NEAT yahoo group as at 2019-10-26 12:00 UTC.
http://groups.yahoo.com/groups/neat
Currently this archive contains only the per-message json result returned by the yahoo API, as such these json files are not in a human readable form. To obtain a human readable form see:
https://github.com/andrewferguson/YahooGroups-Archiver/
make_Yearly_Text_Archive.py
make_Yearly_Text_Archive_html.py
I encountered multiple problems trying to run those scripts, so gave up initially. You may have more luck with one of the forks of that repository, or revising/updating/rewriting the scripts yourself.
The main thing for now is that the messages are archived before yahoo delete them. The stated deletion date is 2019-12-18.
Colin