We collected information on the CEOs and boards of directors of 100 of the largest companies in Finland for specific benchmark years: namely, 1912, 1927, 1938, 1974, 1984, 1994 and 2004. We only included the boards of directors, but not the (non-compulsory ) supervisory boards (hallintoneuvosto/förvaltningsråd ). We selected 100 companies from the manufacturing industry, financial industry, trade and services and the utilities. We collected information about managing directors/ CEOs and boards of directors for these companies. The data for the period before World War II were collected from archival material in the National Board of Patents and Registration and several printed publications (Hjerppe 1979; Banker och Aktiebolag i Finland). After World War II, the sample was based on the list of biggest firms in Finland that is published yearly in the economic weekly magazine, Talouselämä, which has collected and published lists of the biggest companies in Finland since the early 1970s. The information on board members and CEOs was collected from a variety of printed and primary sources. Unfortunately, in the benchmark years 1974, 1984 and 1994, some companies had been omitted because of missing information. The total dataset consisted of 329 firms.
We also look at ‘big linkers’. We focus primarily on the number of positions a person holds. The data from each of the seven sample years were first coded into Pajek (software for network analysis) as a 2-mode network consisting of companies and their board members (De Nooy and Batagelj 2011). The 2-mode network was then transformed into two 1-mode networks, one for the companies and the other for the members of the board. In the 1-mode networks, the businesses are connected to each other by common board members, whereas the directors are connected by having a seat on a board or being a CEO in a specific company.
