Table 2. Annual distribution of the number of publications.

Years	Number of records	Percentage of 1,241
2021	13	1.0
2020	63	5.1
2019	62	5.0
2018	57	4.6
2017	54	4.4
2016	57	4.6
2015	66	5.3
2014	62	5.0
2013	44	3.5
2012	53	4.3
2011	55	4.4
2010	54	4.4
2009	48	3.9
2008	53	4.3
2007	47	3.8
2006	45	3.6
2005	36	2.9
2004	37	3.0
2003	44	3.5
2002	29	2.3
2001	31	2.5
2000	39	3.1
1999	28	2.3
1998	33	2.7
1997	35	2.8
1996	13	1.0
1995	15	1.2
1994	20	1.6
1993	18	1.5
1992	10	0.8
1991	13	1.0
1990	2	0.2
1989	1	0.1
1988	1	0.1
1986	1	0.1
1975	1	0.1
1973	1	0.1

Actual number of literature published each year shown.