share of multilateral environmental agreements by primary subject area, per decennium agreed, cf. fig. 2 in Mitchell et al. (2020), data is also from Mitchell et al. (2020), see sources. Note that treaties are assigned to a year by the year of signature only, whether and for how long the treaties were in force is not taken into account
Own work
User:DeWikiMan, data: Mitchell et al. (2020) (see sources)