When it comes to saving, behavior varies widely among nations. Residents of the United States only save 5.8%. But the residents of 10 countries save more than 9% of their disposable incomes. Economists are uncertain why these countries’ residents save so much more than others. 24/7 Wall St. has analyzed the 10 countries to try to gain insight into the matter.

• Read The Ten Countries Where People Save The Most Money

We reviewed personal savings rate statistics for member countries of the Organization of Economic Cooperation and Development. This information was then compared to the individual tax rate, unemployment rate and actual disposable income, along with the debt and total deficit, for each country.

One factor that could affect the saving rate is a country’s tax rate. The higher the government’s deductions, the less money residents have to spend. Therefore, a significant savings rate in countries with a high tax rates would cause people to have little or no discretionary income. This is indeed true in the case of Portugal and Spain, which have among the lowest tax rates, standing below 20%, and whose residents save among the most. But it’s not always the case. Belgium, for example, has the highest tax rate among the OECD nations, yet its residents still save more than most other countries.

Another reason savings rates vary from country to country may have to do with the fixed cost of living. Americans pay almost $4 a gallon for gas. In some countries, gasoline costs twice that much. People who need to drive a great deal in nations with high energy costs have less to save.

The reasons that people save or don’t save could go on and on. 24/7 Wall St. sought to identify relationships between income and the ability to save. While one might think that high income makes saving more likely; this is not the case. It may be that where people make the most money, the costs of goods and services are proportionately high. It also appears that there is no ready relationship between savings rate and other major economic factors in the countries where people save the most. See for yourselves and let us know what you think.

These are the 10 countries where people save the most money: