Sources of data

For this work, the authors used the balance sheets, the Provincial Statistical Yearbooks, the data from the Early Warning System, as well as the data from the General Population and Housing Census. These were accompanied by value judgements to provide estimates of production and of Value Added. Choosing this procedure is related to the lack of detailed information at provincial level, since the Provincial Statistical Yearbooks, although they have been gradually improving in quality over the years, still have data gaps in certain areas.

Thus for agricultural products, the annual data from the Early Warning System provides information by province for seven major crops (unhusked rice, maize, sorghum, beans, fresh cassava, groundnuts and millet). Taken together, these account for about 75% of the total estimated value of agricultural production in 1996.

As for other products, for which there is no information broken down by provinces, the authors took the weighted average rate of production of the products in the Early W arning System, and, in some cases, the population growth rate, on the assumption that, when the market is saturated and there is no possibility of exports, production becomes stabilised at the size of the market, and its growth, in the case of perishable products, in the absence of other distorting factors, approaches the population growth rate.

For livestock produce, the data on the lists of livestock by province, and by category and species was used. This provides information on cattle, goats, pigs and other species.

For the fisheries sector, the allocation of production to provinces was based on the number of people employed by economic activity, in accordance with the some of the results from IAF 96/97, updated by the population growth rate.

For mining, the source of data was the Ministry of Mineral Resources, which possesses information broken down by provinces on quantities and prices of the main mineral products.

For manufacturing industry, the available data results from the INE's processing of the annual industrial surveys, on the information in the Provincial Statistical Yearbooks, and on the perception of the authors on the location of industrial production.

For electricity, the amount of energy invoiced by provinces, included in the EDM annual reports, was used. For piped water services, the reference data come from the water companies in each province. This information was complemented by the IAF data registering expenditure on water that is not piped. The value is updated annually by the population growth rate, with the assumption that the service bears a direct relation to the number of people who need these services.

For the trade sector, the authors created an index taking into account the number of vehicles, the number of hotel beds, and the number of telephone exchanges, and in this way the production was allocated to provinces.

For the financial sector, staff expenditure (ages and other staff expenditure) was used.

For the construction industry, the authors used the number of people employed by economic activity according to some results of IAF 96/97, and updated with the population growth rate.

For restaurants and hotels, production was allocated according to the guest-nights in hotel establishments, as registered in the Provincial Yearbooks. This criterion is more consistent with that used by the INE's department of national accounts in calculating quantitative indices for the sector.

The distribution of production in the transport and communications sector was based on an index combining statistics of the number of vehicles, cargo handled in the ports, and the capacity used in the telephone exchanges.

For the public administration, health and education sectors, the authors used the expenditure in the state budget, the hospital bed occupation rate, and the number of pupils enrolled.