The platform's datasets are not separate. They join on a handful of keys — the same company number, the same person, the same settlement — and that is what makes it possible to trace which public-procurement contractor also received EU money, or which declaring official also holds a role in the Commerce Registry. The figure beside each pair is measured against the data itself: the number of keys present on both sides.
EIK (company)
Connections graph ↔ EU funds — EU-funds beneficiaries as registered companies. 40,271 shared keys
Connections graph ↔ Public procurement — which procurement contractors are companies in the Commerce Registry. 18,734 shared keys
EU funds ↔ Public procurement — who received both public contracts and EU funds. 5,707 shared keys
Farm subsidies ↔ Public procurement — who takes both farm subsidies and public contracts. 772 shared keys
Connections graph ↔ Health (НЗОК) — hospitals as companies in the Commerce Registry. 256 shared keys
Health (НЗОК) ↔ Public procurement — the hospitals the health fund pays, as procurement buyers. 169 shared keys
Connections graph ↔ Interreg (cross-border) — Bulgarian Interreg partners as registered companies. 121 shared keys
Interreg (cross-border) ↔ Public procurement — Interreg partners who also win public contracts. 42 shared keys
Person
Connections graph ↔ National elections — which candidates also hold company roles. 7,389 shared keys
Connections graph ↔ Officials' declarations — which declaring officials also appear in the Commerce Registry. 5,604 shared keys
National elections ↔ Officials' declarations — which candidates later hold public office. 3,217 shared keys
EKATTE (place)
Connections graph ↔ Maps and boundaries — where companies are registered. 4,080 shared keys of the companies with a resolved seat
Maps and boundaries ↔ Public procurement — which settlement a contracting authority is seated in. 905 shared keys
Maps and boundaries ↔ Interreg (cross-border) — where in the country the cross-border projects land. 160 shared keys of the partner rows with a resolved place
Procedure
EU funds ↔ Open calls — what happened to everyone who applied to this same procedure before. 27 shared keys
Programme
EU funds ↔ Open calls — open calls and what the same programme has already contracted. 12 shared keys
Datasets that must not be merged
Some datasets are related in substance but share no key, and their totals measure different things. Adding them produces a figure no source claims.
EU funds ↔ Interreg (cross-border) — cross-border money, published separately — never add the two totals.
Every link is measured against the data itself — the figure is the number of keys present on both sides. The map is on the data page.