In 1979, this jumped to 36%
In 1980, this fell to 32%
1984 saw a spike to 50%
After this, we saw the rise of the Reform Party. As such, for the next few elections, I am going to compare the combined vote total.
In 1988 the two parties took 45% of the vote, combined. Down 5% from the 1984 PC numbers.
1993, when the Liberals won government, saw this drop to a combined 35%
1997 saw this rise to 38%
2000 saw this hold at 38%
Meanwhile the two parties merged
2004 saw the number dip to 30%, it's lowest share we've yet looked at.
2006 saw it bump to 36%, more traditional levels, but below the average from 1988-2002
2008 saw this rise to 38%
2011 saw a strong showing of 40%
and finally, in 2015, we saw a dip down to 32%
If you adopt an electoral system that eliminates splitting the vote, things can be very good for small-c conservative parties. Two parties can, and I argue would, likely form a government.
Electoral reform is not bad for conservatives.
It's bad for the Conservative Party.
And I don't reforms being bad for any particular party a reason to avoid it.