As it's not needed to have 'other environmental actions' for all years, an alternative would be to have one 'other actions' section in the admin (probably in the artifact section). This could display below the pie graphs on the artifact page, sorted by category rather than year. It could fill the same number of columns as there are years, and if needed there could be multiple categories per column (if there aren't enough years).
If you need more clarification, please let me know!
As it's not needed to have 'other environmental actions' for all years, an alternative would be to have one 'other actions' section in the admin (probably in the artifact section). This could display below the pie graphs on the artifact page, sorted by category rather than year. It could fill the same number of columns as there are years, and if needed there could be multiple categories per column (if there aren't enough years).
If you need more clarification, please let me know!