"In principle, COPNI classifies individual outlays of NPISHs according to the purpose they serve. In most countries, however, there is little information about the activities of NPISHs and so, for practical reasons, the NPISHs themselves will usually constitute the units of classification. Many, perhaps most, NPISHs have a single purpose and can be unambiguously allocated to one of the purposes listed in the classification. Even if a broadly defined NPISH performs two or more functions - such as a religious organization running hospitals and schools as well as organizing religious ceremonies - it will usually be possible to distinguish separate units for each function. If it is not possible to identify a separate unit for each function, or to have an estimation related to each one, then the NPISH as a whole will have to be assigned to the purpose that predominates in terms of employment or total expenditure."