Anyone tracked how defence budget shifts affect commercial aerospace demand?

We've had decent results correlating DoD budget line items (specifically RDT&E and procurement accounts) against commercial MRO spend with a 12-18 month lag — the workforce and supply chain signals tend to bleed across sectors on that timeline. SIPRI and USASpending.gov are your cleanest free data sources to start building that model. The relationship isn't perfectly reliable during geopolitical shocks, but as a leading indicator it holds up reasonably well in normal cycles.