The above analysis of TD method uncertainty impacts the condence in the TD estimation component of MII methods, and oers guidance for calculating these results. Outside an R&D program, most MII programs would utilize only one TD estimate at a time. Therefore, uncertainty in the TD estimate would be inherently dicult to assess using one estimate at each facility. Inventories could be in or out of agreement with TD estimates due solely to uncharacterized uncertainty in the chosen TD method. Further, most reporting programs report only mean values without uncertainty, and have no systematic method to capture uncertainty. Taking the current study as a test case, had all 15 facilities been part of a single report, the aggregate uncertainty in the TD methods, without reference to any inventory methods, would be at least 31% the dierence in the mean estimate of total emissions between the two TD methods.