Explanation:

The trade-to-GDP ratio is an indicator of the relative importance of international trade in the economy of a country. It is calculated by dividing the aggregate value of imports and exports over a period by the gross domestic product for the same period. Although called a ratio, it is usually expressed as a percentage. It is used as a measure of the openness of a country to international trade, and so may also be called the trade openness ratio: 63  It may be seen as an indicator of the degree of globalisation of an economy. 64

Other factors aside, the trade-to-GDP ratio tends to be low in countries with large economies and large populations such as Japan and the United States, and to have a higher value in small economies.: 63 Singapore has the highest trade-to-GDP ratio of any country; between 2008 and 2011 it averaged about 400%