jambon1: A bit similar to how they all dropped in 1976 once it dawned on people that the organisation had led them down the garden path with another false prediction regarding 1975.
Sorry, overall worldwide apparently not...
a very small decrease in 1978 though
1970 = 3,226,168
1971 = 3,453,542
1972 = 3,662,407
1973 = 3,994,924
1974 = 4,550,457
1975 = 4,925,643
1976 = 4,972,571
1977 = 5,107,518
1978 = 5,095,831
1979 = 5,323,766
1980 = 5,726,656
FYI I believe, over the last 80 years, the only years to report an overall worldwide year-on-year decrease in attendance are
1978
1996
1998
2005
2012
2015