In the early 1960s, Canadian economic historian Marvin McInnis started digging through the Dominion Bureau of Statistics archives, looking for city-level information on rental prices. While there, he discovered something strange and disturbing:
A prominent theme of my career has been to reveal anomalies in what has been put forward as evidence. One instance is known only to me. In 1961 I was doing research for my doctoral thesis at what was then called the Dominion Bureau of Statistics. I wanted to know spatial price level differences across Canada. The data were collected for several major cities across the country but only changes over time for those cities were published as the CPI. I wanted geographical differences. I was on good terms with Simon Goldberg, the Assistant Dominion Statistician and he said , OK just go into the archive where the original reports from the cities were stored and dig out what you need. So I did.
What I discovered is that the clerks who recorded the data were under an instruction that, since the CPI was to represent prices paid by better off working class families, to edit out any rental figures what were above a designated threshold. By the end of the 1950s they were throwing out more than half of the reported rents. There had been a serious downward bias in a price that got fairly heavy weight in the CPI. I reported that to Simon but I don't think any alteration was ever made. It was water under the bridge. - Marvin McInnis, personal communication, November 23, 2016