WSTS Blue Book monthly semiconductor billings (1986-2026) by region with 3-month moving average cycle phase classification, Epoch AI GPU shipment volumes (quarterly, H100-equivalent), and BIS export control event markers. Phase algorithm: YoY growth of 3MMA with acceleration/deceleration classification. Anchors when in the cycle a given AI-relevant regulatory action landed: peaks tighten fab utilization caps that constrain near-term AI training infrastructure additions, troughs ease them.
Semiconductor cycle position is a leading indicator for AI compute supply. The industry's 3-4 year boom-bust pattern, shown across four decades, sets fab utilization caps that translate to short-term ceilings on AI training infrastructure additions; cycle troughs ease them. The same cycle anchors the timing of allied export-control rule updates: controls imposed during contractions have different trade effects than those imposed during booms.