The comprehensive 200 page report which is based on Science and Technology Indicators collected by NISTEP comes to the conclusion that the number and quality of refereed papers published by Japanese institutions has declined rather dramatically over the past 20 years. In average of 2013 – 2015, Japan ranked at position 4 of all scientific papers published in the world (1994 and 2004: rank 2), but only at position 9 of the most highly cited scientific papers (1994 and 2004: rank 4). Scientific publications from companies fell from 12 % (1994) to 6 % (2014) of total, and international co-authorship was less compared to other nations. Over the past 20 years, the relative number of papers on physics, chemistry and materials science declined whereas papers on energy/fuels and on medicine/oncology showed the largest relative increase.
https://www.nistep.go.jp/archives/33898