Yet another four legged violator of my subjective, split second interpretation of the 21 Foot Rule, yesterday. Full speed at me, not just standing there, blatantly displaying menacing posture. I had to yank, but I did not crank, because the threat stopped its charge 15 feet from me, thus avoiding being stopped with a tiny amount of time to go. I was the third person to telephone local law enforcement in two minutes to report this threat. They conveyed their concern about my yanking on average of once every 5.5 months, which for me translates into 1,000 miles in my towns' single family residential neighborhoods. I told them that I am not a factor in how often people allow their guard dogs to roam at large on the street to ambush menace people. If once every 52 years, then I will respond appropriately to the threat once every 52 years. If it is 52 times per year, then I will reasonably respond to the threat 52 times per year.