The Ramification Index: RAM Prices, Oligopoly Cycles, and the Downstream Consequences of Semiconductor Pricing as an Economic Signal

Three firms — Samsung, SK hynix, and Micron — control 95% of the world's dynamic random-access memory (DRAM). Their pricing decisions propagate through every layer of the information-technology stack: from server bills of materials to hyperscaler capex to AI-chip allocation to aggregate IT investment. We argue this makes DRAM average selling price (ASP) a structurally superior economic signal to the consumer-demand folk indices that have populated financial journalism for nearly a century. This paper introduces the Ramification Index — the year-on-year log change in the three-firm oligopoly's DRAM ASP. The name borrows from algebraic number theory, where the ramification index measures how a prime ideal branches through a field extension. A DRAM price movement branches the same way: from fab-level pricing into the broader economy. We reconstruct the index annually for 1980–2026 using McCallum's canonical memory-price dataset, Federal Reserve semiconductor price deflator work, and TrendForce contract ASPs. We compare it against the Lipstick Index, the Hemline Index, the Men's Underwear Index, and the Buttered Popcorn Index across six NBER recessions. Results: The Ramification Index identifies all six NBER recessions since 1980, leads the business cycle by one to three quarters, and correlates with real GDP growth at r = +0.41 and unemployment change at r = −0.52. No folk index signals more than four of six recessions, and none achieves |r| > 0.2 against any macroeconomic target. The folk indices measure the leaves. This measures the root. Paper and reproducible code: https://github.com/fromknowware/memory-index