Readers per Copy (RPC) is calculated by dividing the total publication audience/readership (collected with a readership survey like Vividata or the previous ComBase survey) by the number of newspapers delivered (circulation) in the corresponding geography.
Without actual readership data or comparable geographic data, you can use an industry estimate based on the number of adults in the household. This estimate is based on the assumption that once a newspaper is delivered to the home, the adult household members will read it. The average number of adults (based on available public data the closest is age 15+) in the household based on the 2016 census was 2.1 for Canada.
Canada population 15+ (2016 Census) = 29,312,163
Canada private households (2016 Census) = 14,072,080
Average number of household members = 2.1