Diamond's Previews catalog has a bit of a complicated publishing history, at least in terms of the magazine's numbering. The first issue was published in October of 1988 and is most likely unnumbered. (Can anyone clarify?) The following two issues in November and December of 1988 are also unnumbered.

In January of 1989, the publication started numbering issues with #1, the 4th issue overall. The numbering continued for three years through the December 1991 issue, #36, the 39th issue overall.

In January of 1992, the numbering switched to Vol. II, No. 1. The 40th overall issue. A new volume starts in January of every year, and this numbering continues to the present day.

With the January 2008 issue, Previews begins a dual numbering scheme featuring both the volume numbering and a reintroduction of the overall issue number, #232. It should be noted that the overall issue numbering at this point does include the first three, unnumbered issues from 1988.

In order to figure out what the overall issue number is that you should enter for catalogs dated from January 1992 to December 2007, please use the following formula:
( (AA + 1) x 12) + (BB + 3) = Issue number to enter into CBDB
Where AA is the stated Volume Number, and BB is the stated Issue Number.

For example if the catalog in hand is Vol. IX, No. 4, the formula would look like this:
( (9 + 1) x 12) + (4 + 3) = 127
Also, please enter Vol. AA, No. BB into the issue name field.

As for the first 39 issues, they are indexed using the following format.

	nn [1]
	nn [2]
	nn [3]
	1 [4]
	2 [5]
	3 [6]
	[...]
	34 [37]
	35 [38]
	36 [39]

Some other interesting facts about the publication:
• The November 1989 issue, #11, was the first to have a full color cover. Previous covers were two-color.
• The September 1990 issue, #21, was the first squarebound issue. Prior issues were saddle-stitched.
• The January 2008 issue, #232, features a cover gallery of every issue published at that time.
• Marvel was removed from the catalog after issue #78 (March 1995 - Vol. V, No. 3) when it began distribution with Heroes World.
• Marvel returned to Previews with issue #103 (April 1997 - Vol. VII, No. 4).
• The January 1996 issue, #88 (Vol. VI, No. 1), was the first to place the premiere publishers (DC, Dark Horse & Image) at the front of the catalog instead of alphabetically by publisher.