(d) Target relative to the reference indicator, expressed numerically, for example in percentage or amount of reduction Brunei Darussalam is committed to a reduction in GHG emissions by 20% relative to Business-As-Usual levels by 2030. (e) Information on sources of data used in quantifying the reference point(s) Reference indicator will be quantified based on national total GHG emissions in 2015. (f) Information on the circumstances under which the Party may update the values of the reference indicators The national total GHG emissions in 2015 may be recalculated and updated due to continuous methodological improvements. 2. Time frames and/or period for implementation (a) Time frame and/or period for implementation, including start and end date, consistent with any further relevant decision adopted by the Conference of the Parties serving as the meeting of the Parties to the Paris Agreement (CMA); 1 January 2021 â 31 December 2030 (10-year period).