Well, the survey that I mentioned by Will McBride of the Tax Foundation was pretty astounding in including 23 papers written on that subject. It looks at what happens when you make the system more progressive, what it it does to growth rates. I think that by and large most economists would agree that income taxes do the most harm to the economy. Corporate taxes do more damage than the personal tax. If you increase the top rate, you will hurt growth. This comes out in a lot of the studies that have been done. They're cross-sectioned. They look at countries across the world. They also look across different states in the United States. I think the numbers are there.
Anecdotally, or at least by experience, we know that when you are hiring top talent—whether it's young people or people for CEO positions—taxation can play a role. It's not the only thing, but it can play a role. In fact, often companies, when they must bring people into Canada, have to pay equalization to make up for the higher taxes here. That adds to the cost of running the business. If higher rates dissuade people from coming here, because they see Canada as a high-tax country, that will have a negative impact on our talent.
Past studies on talent and the brain drain have shown that there's an impact. The one thing that could be done, which I've never see anyone do, is to look at the income tax forms that the Canada Revenue Agency collects. People indicate on that form whether they've changed provinces and whether they've moved out of the country. They indicate whether they've become a non-resident. It would be nice to start looking at the data to see how taxes might result in people actually moving.
Philip Bazel and I did a paper on the HST in Alberta. We found that until recently, about 25% of the personal income tax base in Alberta was what you might call high-income households, those with more than $500,000 in annual income. That's a lot of money. In fact, it's way beyond any other province.
We know there were many people who, particularly when they got towards retirement, created residency in Alberta. It's not hard to do that, especially if you decide you like skiing. It'll be interesting to see is whether the recent personal income tax hikes in Alberta are leading to a migration of high-income people out of the province.