The required activity data for using a country-specific method (equivalent to a Tier 2 method) for N₂O from manure management, in addition to the data necessary for the livestock characterization, are:

• Annual average nitrogen (N) excretion per head of species/category, adjusted for each age/sex sub-category;
• Fraction of total annual excretion for each livestock species/category that is managed in a different manure management system, which should be the same used to estimate CH₄ emissions from manure management.

If national statistics on the distribution of manure management systems are not available, Parties should conduct a survey.

If the resources are not available to conduct such a survey, the distribution of management system usage may be based on expert advice, or the default values in the Revised 1996 IPCC Guidelines (Appendix B).