The longest period that can occur without a Friday the 13th is fourteen months, either from July to September the following common year (e.g. between 2001–02, 2012–13, and 2018–19), or from August to October the following leap year (e.g. between 1999–2000 or 2027–28).
Friday the 13th can occur as many as three times in a single year; either in February, March and November in an ordinary year (such as 1987), or January, April and July in leap years (such as 2012).
Additionally, a lot of tattoo shops run special deals on Friday the 13th.
Me, personally, I respect tattooing and my clients too much to do $13 tattoos, but I WILL once again be doing a $13 print sale both at the tattoo shop AND here on my website! At midnight on Thursday, 7/12, I will change the prices on ALL my giclee prints from their regular $15-$30 to $13, and my enormous canvas prints from $200 to $130.
24 hours only folks, mark your calendars!