It is often said that Canada and the United States are very much alike, except for the fact that Canada has tons of French people (myself included) and free (TANSTAFL) healthcare. It is also often said that when the US economy catches a cold, Canada gets pneumonia.
From an economic historian’s perspective, this is a hard claim to swallow without making tons of nuances. Yes, economic conditions in Canada are heavily affected by those in the US. But, the evidence for that generally concerns the twentieth century. There is very little before that. The first pieces of evidence we have for Canada start only in the 1870s. In fact, that evidence is also subject to many caveats (my work with Michael Hinton suggests that the GDP deflator for Canada from 1870 to 1900 causes a considerable underestimation of Canadian economic growth during the period and that Canada).
Thus, we do not know if that was always true. To some extent, I am tempted to believe that this is true, but that it is has grown “truer” over time. Canada used to be geared towards Britain and Europe for a long time, but, progressively, it became more connected with the United States. Now, the Maddison project data shows that Canada in terms of GDP per capita converged towards that of the United States from the 1870s to the present day. Morris Altman produced revised estimates of Canadian GDP growth (here) that show a moderately steeper convergence between 1870 and 1929. Given the amount of capital movements between both countries, this is not really surprising (in fact, excluding Quebec from Canada brings the two countries closer together). But again, we don’t go back further than 1870.
So, to see if this is the case, I decided to take my paper (online since yesterday) on creating a price index for Canada since 1688. Measuring Worth offers an American Price Index that starts in 1774. If the two economies began to become more interlinked, then a price index that goes back to the founding of the United States should do the trick. The result is below.
I organized the data by time period and it seems that the rates are generally correlated (which you would expect since global monetary conditions do suggest some long-terms similarities in terms of price trends – I have many reservations about the book I am citing here, but it gets the empirical point across). However, the dispersion seems to collapse over time. As we move from the colonial era to the modern era, inflation rates get more tightly grouped together. Free trade, lower transport costs, central bank policy, capital mobility and labor mobility would have factored in to mean that things become more tightly knit.
It does seem like Canada and the US became more interdependent over time.
I have more to come on this!