In the 1997 report, Science Watch noted that, in the mid-1990s, the sliding U.S. share of world paper output had intersected that of the ascendant EU. As the current graph shows, the trend has continued, with EU nations accounting for 37.93% of the worldwide papers indexed by Thomson Scientific in 2004, up from the region’s initial mark of 33.33% in 1990 (and, not seen on this graph, from 32.26% in 1981, the first year covered in the National Science Indicators database). The EU share, however, does appear to have leveled off in recent years. The United States, meanwhile, accounted for 33.29% of papers in 2004, down from 38.52% in 1990 and 39.68% in 1981. Most striking of all is the rise of the Asia Pacific share, from 15.67% in 1990 (from a 1981 starting point of 13.06%) to 25.32% in 2004. If current trends continue, the Asia Pacific share will likely outstrip that of the United States within six or seven years.

The other graphs tell a similar story—of a U.S. slippage in percent share, a modest overall increase by the EU, and a sharp rise by the Asia Pacific nations. In Physics, the United States slid from 31.00% of Thomson-indexed papers in 1990 to 23.71% in 2004. The EU gained overall, from 32.61% of physics papers in 1990 (despite actually peaking at 40.64% in 2000) to 37.53% in 2004. The Asia Pacific bloc, however, clearly records the sharpest rise, from 20.94% of papers in 1990 to 37.12% in 2004 (more than doubling its percentage of Physics papers from its 15.24% share in 1981). In the graphs depicting Engineering and Materials Science, the scenario is the same: U.S. decline, steady rise by the EU, and steep increase by the Asia Pacific region. The latter is particularly evident in Materials Science, where the Asia Pacific share rose from 25.00% in 1990 (up from 15.07% in 1981) to 43.21% in 2004.

Asia Pacific concentration in the physical sciences is even clearer upon examination of the detailed subfields covered in National Science Indicators. Between 2000 and 2004, authors from this region were most heavily represented in the subfield designated Materials Science & Engineering, having a hand in 54,754 papers, or 42.12% of the 130,004 Thomson-indexed papers published in that field during the five-year period. Metallurgy was next, with Asia Pacific authors contributing to 41.02% of papers, followed by Applied Physics/Condensed Matter/Materials (38.27%) and Electrical & Electronic Engineering (36.24%).

For the EU, the field of highest concentration proved to be Rheumatology, with EU authors contributing to 7,193, or 53.96%, of the 13,331 Thomson-indexed papers in the field. Next among scientific fields came Space Science (52.27%), Endocrinology, Metabolism & Nutrition (48.83%), and Hematology (46.75%). And the United States, aside from its preponderant representation in the Thomson database in social-science fields (e.g., 85.64% of Law papers), saw its highest scientific participation in Aerospace Engineering (50.04%), Cell & Developmental Biology (48.80%), and Space Science (48.47%).

To sum up, in terms of percent share of main subject fields in 2004, the EU and Asia Pacific nations both produced a higher percent share than the United States in the following areas: Agricultural Sciences (EU: 35.99%; AP: 28.15%; U.S.: 25.68%), Chemistry (EU: 37.15%; AP: 33.43%; U.S.: 20.86%), Engineering (EU: 33.93%; AP: 32.26%; U.S.: 29.10%), Materials Science (AP: 43.21%; EU: 32.63%; U.S. 18.50%), and Physics (EU: 37.53%; AP: 37.12%; U.S.: 23.71%). The EU predominated in Clinical Medicine (EU: 40.88%; U.S.: 37.55%; AP: 18.30%), Geosciences (EU: 39.37%; U.S. 35.35%; AP: 24.64%), Mathematics (EU: 45.46%; U.S.: 30.41%; AP: 23.17%), Microbiology (EU: 43.77%; U.S.: 34.75%; AP: 21.81%), Pharmacology (EU: 35.57%; U.S.: 31.03%; AP: 29.63%), Plant & Animal Sciences (EU: 37.31%; U.S.: 30.94%; AP: 23.49%), and Space Science (EU: 53.20%; U.S.: 50.45%; AP: 18.52%).

Although the United States has surrendered a portion of output in these main fields, U.S. citation impact in all these areas remains strong at present. In Physics, for example, for papers published and cited between 2000 and 2004, the cites-per-paper average of U.S. papers was 56% above the world average, compared to 16% above for EU papers and 19% below for those from the Asia Pacific region. The situation is similar in Engineering, where the U.S. average of 31% above the world mark compared with +8% for the EU and -19% for Asia Pacific research.