At 59, you need eight times more light to see at night than you did when you were 20. At 72, you need 16x more light. About 20 percent of American drivers are now over 65. Older drivers
are the fastest growing segment of the driving public.
As we get older, sign letters tend to blur together at night.
The contrast between the letters and the background becomes less apparent.
This effect, called "halation" can be diminished, in part, with larger and/or brighter signs.