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# Mexico

The sources for Mexican national accounts estimates have been more carefully described than those of our other countries. For the period 197078, there is a massive 8 volume study (SPP, 1981) prepared by the Mexican authorities with the help of a team of foreign experts. This study is a major revision of the national accounts, with increases in the estimates of GDP level, and changes in growth of real product. The two volumes on manufacturing contain 1,441 pages of statistics and source description. These permit a detailed confrontation by branch of gross values, input values, value added, wages and salaries, indirect taxes, gross profits and employment with the figures in the tenth industrial census in Mexico (SPP, 1979a and 1979b). Mexico also has an input-output table for 1975 (table 2.5 below).

The national accounts estimate of manufactur'lng value added for 1975 is 38 per cent higher than that of the census when one adds petroleum refining, which is excluded from the census because output is largely confined to one government enterprise, PEMEX. The differences by branch can be seen in detail in table 2.3 in which the industrial census figures are adjusted to the same conceptual basis as the national accounts, the difference between the two sources being due to inadequate coverage of informal activity in the industrial census. The national accounts estimates are based on a variety of sources including the census, and in many cases it is explicitly stated that output is inadequately covered in the census. The ratio of the national accounts estimates to the census figures varies considerably from industry to industry. For food products, the national accounts figure is 229.7 per cent of the census, whereas for primary metals and metal products it is lower than that of the census. The underestimation in the census does not seem to be confined to small establishments. One can infer this from the fact that output per person employed is generally lower in the census than in the national accounts figures. One usually expects small firms to have lower labour productivity than big ones (see table 2.4). The paradoxical productivity figures for the informal sector may be due to the fact that the national accounts includes only paid employees, whereas in the informal sector there is probably a fairly high proportion of unpaid family workers.

The Mexican census definition of gross value added, "Valor Aggregado Censal Bruto" is netter than the Brazilian "Valor de Transformacao Industrial" or the US census definition. However, the census contains enough informaUion to arrive at an estimate of value added which corresponds with the national accounts concept or to one which corresponds with the Brazilian and US industrial census definitions. As in Brazil, the Mexican output figures refer to production including output which goes to inventory, whereas US figures refer to shipments. The Mexican value figures in some cases include indirect taxes. The most notable cases, for which we have made a correction are alcoholic beverages and tobacco and tobacco products where the incidence of excise taxes was 28.1 and 192.7 per cent (see table 2.3). For petroleum refining and products we also deducted indirect taxes, which we derived from national accounts information. Elsewhere we did not think this problem was significant.