The election : 2016 easily
The year: 2006 pretty easily
The whole 2000s are probably the most Conservative Decade we have had since the 1920s
The 1980s too were so conservative with the Reagan Revolution, Theresa May in the United Kingdom and Brian Mulroney in Canada, notably.
Speaking as a Canadian, it's really quite misleading to lump in Mulroney with Reagan and Thatcher. I see this done a lot, I'm guessing because he was a Conservative who held office in the 1980s, but the issue is Mulroney was much much more moderate than either of them. To give 2 examples, Mulroney is often called "Canada's Greenest Prime Minister" (in fact, current Green Party leader Elizabeth May served as an advisor to Mulroney), and he did little to break the backs of labour.