purchasing power of disparate types of prices. Although the ICP has not calculated military sector PPPs, a proposal for research on means to estimate SuCh rates has been made to the United Nations group of experts studying the relationship between disarmament and development. Such estimates would be made on the basis of the detailed categories for which PPPs have already been estimated and on othcr data. 117. Althou@ a ful1 solution to the conversion problem may not be irmninent, the complexity of the problem, the length of time likely to be required for a solution, and the existence of the related ICP research, suggest that the time is at hand to ínitiate an international effort to resolve the problem of currency conversion as applied to military expenditures. Intertemporal comparisons 118, In view of the tendency for prices to change, comparisons of military expenditures over time require appropriate price indexes for the things purchased. Indexes calculated specifically for military g00as are, in most countries, generally unavailable. Recourse may be had to surrogate indexes for other goods, but the resulting estimates of %eel" expenditures suffer to the extent such surrogates diverge from what a true index would be. 119. In the report of the group of experts in 1976 (A/31/222/Rev.l), this question is discussed at some length. Possible ways of constructing a military price index are described together with the difficulties of finding accurate statistical data, It is recognized that the issue is not purely technical but has a strong political nature, as the kind of index chosen or composed will have an important impact on the actual rate at which agreed reductions of military expenditures will have to be carried out. 120. The outline for constructíng a weighted price index for the military sector as proposed in the 1976 report is very ambitious. Nevertheless, as it 
**Analysis**
The text discusses the purchasing power parity (PPP) of military expenditures and the challenges of converting military expenditures from one currency to another. It also touches on the need for a military price index to make intertemporal comparisons of military expenditures. The text seems to be focused on economic issues related to military spending and its measurement.

**Category**
Economic development, International trade