There are no issues of 72-79. Editors created a jump in issue numbering from issue 70 to issue 80 in 1970. They did this (according to the editorial in issue 80) because it brought them closer to issue 100, justifying the numerical jump with the ten issues of the short-lived companion magazine Monster World as issues that "would have been" Famous Monsters issues. Issue #71 was done in 2011 using the old numbering, with a modern cover price.
Issues #115 and 119 confirmed to have no comic content.