A new report set tongues wagging Wednesday for its back-of-the-envelope calculation that estimated of the $38 billion in Vancouver residential real estate sales in 2015, Chinese buyers were responsible for a third.

By comparison, the report said Chinese investors accounted for $9 billion of the $63 billion in deals in Toronto or 14 per cent of the purchase volume.

National Bank of Canada financial analyst Peter Routledge’s calculation is based on deriving “inferences or hypotheses” for Canada from the U.S. National Association of Realtors, which produces an annual profile of home buying activity by international investors. There is no such data collected in Canada.

The NAR’s definition of an international buyer includes non-resident foreigners and resident foreigners — that is a recent immigrant (who has been in the country for less than two years) or a temporary visa holder (who has been living in the country for at least six months).

He found the NAR estimates Chinese buyers invested $US 28.6 billion in U.S.-domiciled residential real estate properties over the 12 months ending March 31, 2015, up from just $4.1 billion in 2009.

To figure out what an equivalent purchase volume for buyers from China in Toronto and Vancouver might be, Routledge looked for “useful survey data from which we can draw reasonable hypotheses” and found it in a Financial Times multiple choice survey of 77 high net worth and affluent mainland Chinese individuals, “admittedly not a statistically significant sample size,” he acknowledged. The survey found that of those who purchased residential real estate outside China, 33.5 per cent had done so in the United States (mainly in New York, Los Angeles, and also San Francisco) while 11.7 per cent bought in Vancouver and 8.3 per cent in Toronto.

From this, “one could hypothesize that for every four high net worth buyers from China who purchase a U.S. residence, one purchases a residence in Toronto; and, for every three high net worth investors from China who purchase a U.S. residence, one purchases a residence in Vancouver.”

Applying these ratios to the NAR estimate of $28.6 billion US in the U.S. residential real estate investment made by buyers from China, he came up with the number of $12.7 billion CDN invested in the Vancouver residential real estate market by buyers from China, an amount that is 33 per cent of the total volume.

Routledge cautioned: “The estimated share of purchase volume seems high and we stress this methodology is truly a back-of-the-envelope attempt at gauging the significance of capital inflows from mainland China on the local residential real estate markets in Toronto and Vancouver. The surveys upon which we base our hypotheses could have built-in biases that overstate (or understate) the amount of capital inflows into Canadian and U.S. residential real estate markets.”

Routledge, who worked on the report with associates Parham Fini and Paul Poon, was not available for comment.

The report is based on NAR numbers ending March 31, 2015 so they would not take into account some of the significant outflows of Chinese capital that happened in the last three quarters of 2015, including a surge in the last few months.