Table 4.

Patterns of coauthorship by type of coauthor and year

Year	SELF	Public	NIH	University	Hospital	Nonprofit	Private	Miscellaneous	Total
80	0.69	0.02	0.02	0.20	0.04	0.01	0.01	0.01	2,050
81	0.67	0.02	0.01	0.21	0.05	0.02	0.02	0.00	2,200
82	0.62	0.02	0.02	0.26	0.05	0.02	0.02	0.01	2,702
83	0.62	0.02	0.02	0.23	0.07	0.02	0.02	0.01	2,992
84	0.58	0.03	0.01	0.25	0.08	0.03	0.02	0.01	3,023
85	0.60	0.02	0.01	0.25	0.07	0.02	0.02	0.00	3,834
86	0.57	0.02	0.01	0.26	0.08	0.02	0.03	0.01	3,928
87	0.57	0.02	0.01	0.28	0.07	0.02	0.02	0.01	4,535
88	0.58	0.02	0.02	0.27	0.06	0.02	0.02	0.01	4,312
89	0.55	0.02	0.01	0.30	0.07	0.02	0.02	0.01	4,032
90	0.56	0.02	0.02	0.28	0.07	0.02	0.03	0.01	5,147
91	0.53	0.03	0.01	0.30	0.06	0.02	0.04	0.01	6,260
92	0.54	0.03	0.01	0.29	0.06	0.03	0.04	0.01	7,611
93	0.53	0.03	0.01	0.29	0.06	0.02	0.04	0.01	8,293
94	0.53	0.03	0.01	0.30	0.06	0.03	0.03	0.01	8,410
Total	39,175	1,780	922	19,074	4,345	1,541	2,031	483	69,239

Table entries are the fraction of instances each type of institution appears that year as an address of a coauthor on a paper published by one of the firms in the data set. The last column gives the number of instances of coauthorship that year. The last row gives totals by type of coauthor over all years.