1. "...some markets seem to be less in tune with the dips and advances of the S&P 500 than others. In particular, three country ETFs stand out as exhibiting a relatively low correlation with the S&P over the past two years..."
2. Levels of Public Debt as a % of GDP from 2009, a list by country
3. put 'em together and you get: "five ETFs [OK, three] focused on countries with low debt-to-GDP ratios"