(g) An item is a specific model within a type. In the case of aircraft and engines, an item could, for instance, be a particular fighter aircraft such as F5, F16, etc.; (h) A unit is one single entity of a particular item, such as one F16-fighter aircraft; (i) A characteristic is a quality used to describe a particular item with special regard to its military utility. Qualities of little or no importance to the military utility of an item should not be regarded as characteristicsr (j) Military expenditures are those that are to be reported within the United Nations system for standardized international reporting of military expenditures. Such expenditures may differ from the social costs involved because of several reasons, such as non-market wages to conscripts , abnormal profits in the defence industry, State subsidies and others; / . . . A/40/421 English Page 70 (k) A unit price is the total expenditures made for an item divided by the number of units. For further specification, see paragraph (PI, below. The price may not reflect the social costs; (1) The period of the exercise covers the three fiscal years most closely corresponding to the calendar years 1980-1982. Guidelines (a) Information should be restricted to such items that were actually delivered during, at least, one of the three fiscal'years within the period of the exercise. YOU need not report on more than four items within each type. In case you would have more than four items to report on , please select those items on which you spent most; (b) Price information to be submitted should be actual unit prices where these are readily available , or estimated unit prices in cases where these can be prepared with a reasonable effort and with relative accuracy (that is, within an expected margin of plus-or-minus 10 per cent)1 
**Analysis**
The text appears to be discussing the reporting of military expenditures and the classification of items, units, and characteristics related to military equipment. The language used is technical and specific to the military sector, suggesting that the text is related to the reporting of military spending and inventory. The text does not mention any specific economic development goals or environmental concerns, which are typical of the other categories.

**Category**
Industry, Transport and communication