You may have heard of the 6-second rule when it comes to how much time we have to spend looking at an advertising billboard while driving by. Or the fact that you should stick to 7 words or less. At 55 mph that’s all the time you have! Back in 1835, when billboards began to appear on our roadways, the average vehicle speed was about 8 to 10 mph. Which ups the word limit to about 60, or enough to tell a pretty good story.