You're likely to have more. I would only notice when one was coming on when I was at my computer. The monitor seemed to get a little blurry, then after a short time, the small blinking object appeared.

The regularity with which I had them varied greatly. I kept a log for a while....once a year, twice a year, three times in one month, then nothing for the rest of the year. They lasted for about eight years.

The best one was the one that hit while I was driving on the beltway in Washington D.C. Good thing I can filter things out pretty well.