I have found some discrepancies in the numbering system as far as volume number go.
Since the publication started in 1981 I would assume that would be volume #1, but the 1985 issue shows Vol1.

Here is the list I went through to name these:

Year	Volume
1981	1
1982	2
1983	3
1984	4
1985	5
1986	6
1987	7
1988	8
1989	9
1990	10
1991	11
1992	12
1993	13
1994	14
1995	15
1996	16
1997	17
1998	18
1999	19
2000	20
2001	21
2002	22
2003	23
2004	24
2005	25
2006	26
2007	27
2008	28
2009	29
2010	30
2011	31
2012	32
2013	33
2014	34
2015	35
2016	36
2017	37
2018	38
2019	39