Five spatial scales
Five spatial levels, one architecture — and where the cross-border story changes.
Five spatial scales
The balance-sheet identity holds at every territorial level — country, state, county, and below. The architecture does not change as you descend; what changes is the meaning of cross-border, and that is where the most interesting empirical content lives.
The five scales
| Scale | What | Coverage |
|---|---|---|
| TL1 | Country | 200+ countries, 1950–2025 |
| TL2 | US state | 51 states + DC |
| TL3 | US county | ~3,258 counties |
| Tract | Census tract | Roadmap — drives commuter-flow analysis |
| Block group | Census block group | Roadmap — the smallest unit at which the identity still closes |
TL1 is complete and verified; the US subnational exercise extends the same balance sheet down to TL2 and TL3, proving the architecture works at every level. Tract and block group are on the roadmap.
The two-version architecture for the United States
The US appears twice, distinguished by identifier system — and the gap between the two records is a measurement:
iso3 = USA(TL1) — internationally comparable, top-down. The reference.fips = 00000(bottom-up) — the US rebuilt from its counties up, enriched with jurisdiction-specific liabilities (intergenerational accounts, local institutional knowledge) that only exist where national statistical systems report them.
The bottom-up Commonwealth runs +5.9% above the TL1 reference (a net-debtor ownership position the international view misses), while bottom-up Natural Capital lands −24.8% below it (county allocation undershoots the national figure). The difference between the two is the empirical content of local institutional knowledge — see US states.
What cross-border means at each scale
| Scale | Cross-border story | Magnitude |
|---|---|---|
| Country | International — foreign assets vs foreign liabilities (IMF data). | USA net position ≈ −$15 trillion |
| State | International plus interstate — where people live vs where they work across state lines. | 13–399× larger than the international flow for commuter-belt states |
| County | Commuter flows dominate — income earned in one county, spent in another. | The defining relationship at this scale |
At the country level cross-border is a footnote to a mostly-closed economy; by the county level it is the headline. The identity absorbs all of it without changing shape.
What stays invariant across scales
The same engine powers 200 countries and the US deep dive because a fixed core is shared at every level:
- the balance-sheet identity;
- the What classification codes;
- the HR regression coefficients (invariant across TL1/TL2/TL3);
- the valuation parameters (discount rate, severance rate, …);
- the frame architecture and tab homology.
What is country-specific
Loaded from configuration, not hardcoded:
- source agencies (BEA vs IMF, BLS vs ILO, …);
- entity gazetteers (FIPS vs ISO 3166);
- allocation methods;
- temporal coverage.
This universal-vs-specific separation is what lets one architecture serve every territorial level and every country without forking the model.