More than 1,000 issues were published, usually with multiple titles released every month. An exact accounting of the actual number of unique issues produced is difficult because occasional issue numbers were skipped and a number of reprint issues were also included, although the Overstreet Comic Book Price Guide nonetheless lists well over 1,000 individual issues, ending with #1354, but some numbers were skipped. It currently holds the record for most issues produced of an American comic book; its nearest rivals, Action Comics and Detective Comics, both still publishing monthly issues after more than 70 years, only recently passed their 800th issues. The first 25 issues are known as "series 1"; after they were published, the numbering began again and "series 2" began. Four Color is notable