20.90 出版物方面出现差异是林业和木材研究论文造成的，这是因为规划工作目前每年进行一次，而不是每年两次，并且本次级方案以前在两年期内的出版物数目是 13 份。
20.90 The variance in publications is driven by forestry and timber study papers, owing to the fact that planning is now done on an annual instead of a biannual basis, and the subprogramme ’s number of publications used to be 13 for the biennium.