Great news. Recent data indicate that the incindence of macular degeneration is decreasing. in 1996, 9.4% of USA adults were found to have macu;ar degeneration (in a study involving 7000 volunteers). A 2009 analysis determined otherwise — only 2.5%. the decreasing prevalence, if confirmed by additional studies, reflects, one can assume, a change in the freqnency of smoking, and of exposures to dietary sodium, cholestrol, and blood pressure.