3. The Aggregate Turnover of Advanced Capital. Cycles of Turnover

We have seen that the fixed and circulating component parts of productive capital are turned over in various ways and at various periods, also that the different constituents of the fixed capital of a business have different periods of turnover, depending on their different durability and therefore on their different times of reproduction.

1) The aggregate turnover of an advanced capital is the average turnover of its various constituent parts. Inasmuch as it is merely a question of different periods of time, nothing is easier than to compute their average. But

2) We have here not alone quantitative but also qualitative difference. The circulating capital entering into the process of production transfers its entire value to the product and must therefore be continually replaced in kind by the sale of the product, if the process of production is to proceed without interruption. The fixed capital entering into the process of production transfers only a part of its value (the wear and tear) to the product and despite this wear and tear continues functioning in the process of production. Therefore it need not be replaced in kind until the lapse of intervals of various duration, at any rate not as frequently as the circulating capital. This necessity of replacement, the reproduction term, is not only quantitatively different for the various constituent parts of fixed capital, but, as we have seen, a part of the perennial fixed capital, that which lasts longer, may be replaced annually or at shorter intervals and added in kind to the old fixed capital. In the case of fixed capital of different properties the replacement can take place only all at once at the end of its period of durability.

It is therefore necessary to reduce the specific turnovers of the various parts of fixed capital to a homogeneous form of turnover, so that they will remain different only quantitatively, namely, according to duration of turnover.

3) It follows that even if by far the greater part of the advanced productive capital consists of fixed capital whose period of reproduction, hence also of turnover, comprises a cycle of many years, the capital-value turned over during the year may, on account of the repeated turnovers of the circulating capital within the same year, be larger than the aggregate value of the advanced capital.

4) Therefore the turnover time of the value of the advanced capital differs from its actual time of reproduction or from the actual time of turnover of its component parts. Take for instance a capital of £4,000 and let it turn over, say, five times a year. The turned-over capital is then five times £4,000, or £20,000. But what returns at the end of each turnover to be advanced anew is the originally advanced capital of £4,000. Its magnitude is not changed by the number of turnover periods, during which it performs anew its functions as capital.

4. The Turnover of Variable Capital. The Annual Rate and mass of Surplus-Value.

The variable circulating capital expended in production can serve afresh in the process of circulation only to the extent that the product in which its value is reproduced has been sold, converted from a commodity-capital into a money-capital, in order to be once more laid out in payment of labour-power. But the same is true of the constant circulating capital (materials of production) invested in production, the value of which reappears in the product as a portion of its value. What these two portions — the variable and the constant part of the circulating capital — have in common and what distinguishes them from the fixed capital is not that the value transferred from them to the product is circulated by the commodity-capital, i.e., through the circulation of the product as a commodity. One portion of the value of the product, and thus of the product circulating as a commodity, of the commodity-capital, always consists of the wear and tear of the fixed capital, that is to say, of that portion of the value of the fixed capital which is transferred to the product during the process of production. The difference is really this: The fixed capital continues to function in the process of production in its old use-form for a longer or shorter cycle of turnover periods of the circulating capital (equal to constant circulating plus variable circulating capital), while every single turnover is conditioned on the replacement of the entire circulating capital passing from the sphere of production — in the form of commodity-capital — into the sphere of circulation. The constant circulating and variable circulating capital have the first phase of circulation, C' — M, in common. In the second phase they separate. The money into which the commodity is reconverted is in part transformed into a productive supply (constant circulating capital). Depending on the different terms of purchase of its constituent parts, one portion of the money may sooner, another later, be converted from money into materials of production, but finally it is wholly consumed that way. Another portion of the money realized by the sale of the commodity is held in the form of a money-supply, in order to be gradually expended in the payment of the labour-power incorporated in the process of production. This part constitutes the variable circulating capital. Nevertheless the entire replacement of either portion always originates from the turnover of capital, from its conversion into a product, from a product into a commodity, from a commodity into money. This is the reason why, in the preceding chapter, the turnover of the circulating capital, constant and variable, was treated jointly and separately without paying any regard to the fixed capital.

The variable capital turned over during one year — hence the portion of the annual product, or of the annual expenditure equal to that portion — is the variable capital actually employed, productively consumed, during that year. It follows therefore that if the variable capital A turned over annually and the variable capital B turned over annually are equal and the employed under equal conditions of self-expansion, so that the rate of surplus-value is the same for both of them, then the quantity of surplus-value produced annually must likewise be the same for both of them. Hence the rate of surplus-value calculated for a year must also be the same, since the amounts of capital employed are the same, so far as the rate is expressed by (quantity of surplus-value produced annually) / (variable capital turned over annually). Or, expressed generally: Whatever the relative magnitude of the turned-over variable capitals, the rate of the surplus-value produced by them in the course of the year is determined by the rate of surplus-value at which the respective capitals have worked in average periods (say, the average of a week or day).

This is the only consequence of the laws of production of surplus-value and of the determination of the rate of surplus-value.

Let us see further what is expressed by the ratio