20.25 实质性会议服务方面出现差异的主要是原因如下：(a) 环境政策委员会和附属机构的会议，原因是委员会决定将其 2018 年年度会议改在 2019 年 1 月举行；(b) 《在环境问题上获得信息、公众参与决策和诉诸法律的公约》缔约方会议，原因是缔约方就 2018-2021 年工作方案作出的决定导致公众参与决策问题工作队 2018 年会议天数减少。
20.25 The variance in substantive services for meetings was driven mainly by: (a) meetings of the Committee on Environmental Policy and subsidiary bodies, owing to the decision of the Committee to move its 2018 annual session to January 2019; and (b) the Meeting of the Parties to the Convention on Access to Information, Public Participation in Decision-making and Access to Justice in Environmental Matters, owing to the decision of the parties on the work programme f or 2018–2021, which resulted in a decrease in the number of meeting days of the Task Force on Public Participation in Decision-making in 2018.