Animal Spirits Under Radical Uncertainty: Natality as a Long-Horizon Register of Collective Optimism

This dataset explores Keynes's concept of animal spirits through long-horizon collective optimism using historical monthly demographic records from Sweden (1851–2024) and Finland (1888–2024). Proposing natality as a behavioral expression of forward-looking commitment under radical uncertainty, the combined Nordic data isolates a prominent, low-frequency spectral feature near 21.7 years. The repository and replication scripts support a Post-Keynesian research agenda examining deep-rooted behavioral commitments. For the full abstract text, please refer to the referenced document.