Housing Prices - Further to Fall?

A couple weeks ago, The Economist ran a story on housing prices which stated that a number of developed countries (the United States was a notable exception) faced significant decline in prices in order to realign them with long run historical averages.  It included a table summarizing their results (at the bottom, click for a larger image).  The long run historical average used tp determine the implied declines was the price-to-rent ratios, which differ from country to country.  While there is certainly an argument that the long-run average should persist, I believe that there is a much more thought-provoking argument that there may be a structural break in the price-to-rent ratio.

The fact that the long run average price-to-rent ratio differs from country to country forms the basis for my argument.  A number of factors could influence this ratio across countries, such as differences in the difficulty/ease of obtaining financing, differences in marginal utility of owning a house versus renting, differences in available investment opportunities (China?), etcetera.  Each of these factors is in turn influenced by a number of other factors, ranging from the social to the political, with the result being a host of factors influencing the price-to-rent ratio.  The Economist does not give the long run average price-to-rent ratio in each country, but I suspect that it could be quite wide ranging (otherwise they would not differentiate between countries).  Assuming changes in geography dictate a considerable range in price-to-rent ratios, I am positing that the factors which influence this ratio may undergo permanent change over the short term, thereby introducing a structural break to the price-to-rent ratio.  The long term is generally defined as at least 25 years.  Consider the changes in the social, economic and political landscape which have occurred over the last 25 years in some of these countries.  Quantifying some of the relevant measures and crunching the numbers would prove enormously time consuming, but I suspect would add significant value, as The Economist is calling for a significant fall in Hong Kong, Australia, Spain, and France, among other markets.  Let us not forget one of (my) primary takeaways from in Rienhart and Rogoff's "This Time is Different": property market busts are often precursors of financial crises.