Estimates of the number of the world's researchers provide broad support for the trends and shifts suggested by R&D and degree data.
The estimated number of researchers grew from nearly 4 million in 1995 to about 6 million in 2008. The United States and the 27 EU-member countries accounted for about 1.4 and 1.5 million researchers each—a combined 49% of the total but below the 51% share they had held a decade earlier. China's researchers tripled over the period.
Trends in researcher growth rates vary greatly by country and region (figure
The contribution of multinational corporations to researcher growth in the overseas markets in which they operate is unknown. But preliminary data, available every 5 years, suggest a pronounced expansion of R&D employment by overseas affiliates (majority-owned only) of U.S.-based MNCs in recent years. After gradually increasing from 102,000 in 1994 to 138,000 in 2004, their R&D employment almost doubled to 267,000 in 2009. Over the same 5 years, the MNCs's R&D employment in the United States rose from about 716,000 to about 739,000. This boosted the overseas share of their total R&D employment from 16% to 27% (figure
Data on employment of researchers by foreign-based MNCs in other countries are unavailable, except for those working in the United States. Growth in U.S. employment of researchers working for U.S. affiliates of foreign-based MNCs has been broadly in line with overall U.S. researcher trends.