Differential Accumulation is an approach for analysing capitalist development and crisis, tying together mergers and acquisitions, stagflation and globalization as integral facets of accumulation. The concept has been developed by Jonathan Nitzan and Shimshon Bichler.
The concept of differential accumulation emphasizes the powerful drive by dominant capital groups to beat the average and exceed the normal rate of return. This concept is tied to a definition of capital as a social category rather than a material category (as seen by neo-classical thinkers). "Capitalism is not an ‘economic system’, but a whole social order, and its principal category of capital must therefore have an ‘encompassing’ definition."
...capitalization is a forward-looking process. What is being accumulated are claims on the future flow of profit. The pace of accumulation therefore depends on two factors: (a) the institutional arrangements affecting profit expectations; and (b) the normal rate of return used to discount them into their present value. The effect of rising industrial capacity on these factors is not only highly complex and possibly non-linear, but its direction can be positive as well as negative. But then if capital is not ‘tangible’, how should its accumulation be measured? Surely, the mere augmentation of money values tells us little about power, particularly in the presence of inflation or deflation. The answer is rooted in the relative nature of power. The power of the absentee owner is the power to control part of the social process, and that becomes meaningful primarily against the power of other owners.
A firm can raise its profit through "breadth" by adding more employees to the organization. Conversely the firm can pursue "depth" by generating higher profit per employee. Each avenue of breadth and depth can be divided into pursuing differential accumulation through "internal" or "external" means. This gives us four categories of differential accumulation: internal breadth by amalgamation (buy or join other businesses), external breadth through greenfield investment (build new factories), internal depth via cost-cutting (make workers work harder or find ways to reduce the price of inputs), and external depth through stagflation (raise prices faster than the competition).