The inventory cycle: why warehouses move output more than demand itself

The inventory cycle is a swing in production that arises not from a change in demand but from the way firms adjust their stocks to it. A manufacturer does not order exactly as much as it sells; it orders as much as it expects to sell, plus or minus a correction that brings its inventory back to the desired level. That is why a small, even temporary, shift in final demand travels up the supply chain and gets amplified along the way, and why in the national accounts it is not the level of inventories that enters output but their change. Hence the main counterintuitive conclusion: inventories do not have to fall in order to subtract from growth — it is enough for them to stop growing at their previous pace. A warehouse that has merely stabilised is already a drag on the economy.

Why the supply chain amplifies the signal

Between the shopper in a store and the mine there are several links, and each of them holds its own buffer. When a retailer sees sales accelerate, it raises its orders not only to cover the extra sales but also to replenish its buffer for the new, higher turnover. The distributor, on receiving the larger order, does the same with its own warehouse. By the time the signal reaches the start of the chain, it arrives noticeably distorted and delayed — this is the bullwhip effect. At the turning point the mechanism works in reverse, and more harshly: when demand cools, each link first sells off what it has accumulated and only then resumes purchasing, so orders to the manufacturer dry up long before final demand has actually dropped.

The phases of the cycle are usually distinguished as follows: voluntary stockbuilding on expectations of growth; involuntary stockbuilding, when sales have already slowed but contracted orders keep arriving; destocking, with purchases halted; and a recovery in orders once inventory falls below a comfortable level. The most painful phase for output is destocking; the most deceptive for an investor is involuntary stockbuilding: revenue still looks decent, but the warehouse is already flashing a warning.

How the phase of the cycle shows up in financial statements

The macro phase is easier to identify from the bottom up, company by company, than from the top down. A practical technique is to compare the growth rate of inventories with the growth rate of revenue in the same set of accounts: if inventories are growing faster than sales, the company is entering involuntary stockbuilding, and the next casualties will be its margin (discounts to clear the warehouse) and its free cash flow (money tied up in goods). The opposite picture — inventories shrinking faster than revenue — often precedes a recovery in orders placed with suppliers.

The formal measure of this relationship is inventory turnover; how it is calculated and what its pitfalls are is covered in the glossary entry, and the data themselves come from issuer disclosures. It pays to look at the links of the chain separately: retail, distribution, intermediate processing and raw materials. The turn in the raw-materials link becomes visible last of all, and that is precisely why a decision taken on the basis of commodity headlines is often taken as the phase is already running out.

What the cycle does to prices and interest rates

Destocking is disinflationary by mechanism, not by coincidence: goods are sold off at a discount, there are no new orders, and pressure on purchase prices eases. That is why the destocking phase often brings a slowdown in goods inflation that should not be mistaken for a lasting one — a recovery in orders brings price pressure back. For the debt market, this means that disinflation "from the warehouse" and disinflation from cooling demand are different stories with different staying power; the OFZ curve and the rest of the bond market react to them differently. For equities, the inventory cycle is first and foremost a cycle of margins and working capital in cyclical industries rather than a revenue cycle; a selection of securities by sector is available in the equities section.

What it does not explain

The inventory cycle is short and shallow by nature: it is a correction of buffers, not a shift in the investment or credit cycle. It should not be used to explain multi-year trends, structural shifts within an industry or a reorganisation of logistics — other mechanisms are at work there, and attributing them to inventories leads to expectations of a quick return to normal that will not materialise. The opposite mistake also occurs: a prolonged deterioration in results is written off as a "one-off inventory clear-out" quarter after quarter.

A fair caveat: the platform does not publish a single ready-made indicator of the inventory-cycle phase for the Russian economy, and this article contains no third-party estimates that are not in its database. You have to assemble the picture yourself — from the financial statements of each link in the chain, from the sector news flow and from the events calendar, so that you know publication dates in advance and do not trade on what has already been priced in.