The third quarter of 2015 was also the first quarter that interprovincial net inmigration into Ontario was positive, and Petramala et al believe that much of this inmigration was to Toronto’s benefit, pushing up the demand for houses. July 2015 was also the month that the Bank of Canada dropped the overnight rate to 0.5%, after reducing it to 0.75% in January. Petramala and company come down squarely on the clean side in the “lean vs clean” debate. They don’t believe the central bank should lean against housing bubbles; instead it should just busy itself with cleaning up the mess afterwards, even if the mess was in large part created by its own interest rate reductions.