1968
1982,
1983,
1993,
1994,
2008,WF
2011WF,
2014,SW
2014,WF
2015,SW
The above list is all of meets that were cancelled since SW started i 1949.
I don't have the USFRA or other Org. that were rained out over the years.
The first world final meet was 1991 and was a LSA meet. LSA didn't go very long and was dropped.