Does anyone know the significance of the date 9-11-1961? The password list has 10,444 matches for "9-11-1961" and 10,231 for "9111961".

From Wikipedia, I see that Hurricane Carla hit Texas that day but that doesn't seem noteworthy enough to warrant two instances of the date in the top 20, It would be surprising if it was only due to date of birth too, given I can't spot any other date-like entries.