When General Aviation was affordable

Although aviation has always been an expensive pursuit, it was at least affordable until about 30 years ago. In 1978 over 18,000 new airplanes were delivered but by1986 that number had dwindled to just over 4,000 aircraft. In 1994 only 928 units were delivered. Here is my 2 cent view on some of the things that drove the cost up. What say you?