New research on road accidents shows this Friday the 13th could be an especially unlucky day for motorists.
Analysis from the AA and the Work Wise UK organisation reveals that when Friday - the worst day for casualties - is combined with November - typically a bad month for accidents - the risk of crashes is high.
Overall, road casualty numbers rise 10% on a Friday, compared to the rest of the week. From 2pm to 5pm on Fridays and in the early evening, road casualties are up to 20% higher than the average for other weekdays.
But the AA also said that Fridays could be developing a new twist, courtesy of changing working practices.
The morning rush hours and 5-6pm period is becoming safer.
AA president Edmund King said: "Since the turn of the millennium, Fridays have become safer, and more like the other weekdays. This could show a change in working practices, with more people working from home and choosing to do so on Friday.
"Alternatively, they may start early during the week and take off on Friday afternoon."
"Hopefully, the future will see the positive aspects of these new work patterns move to the rest of the week. However, at the moment, Fridays are still dangerous, and this Friday the 13th has all the ingredients to be particularly so. Take care with what we have dubbed the Fatal Friday Phenomenon."
© Press Association 2009