Clusters or networks of economies? A macroeconomy study through Gross Domestic Product

We study correlations between web-downloaded gross domestic product (GDP)'s of rich countries. GDP is used as wealth signatures of the country economical state. We calculate the yearly fluctuations of the GDP. We look for forward and backward correlations between such fluctuations. The correlation measure is based on the Theil index. The system is represented by an evolving weighted network, nodes being the GDP fluctuations (or countries) at different times.