ASEAN is a geo-political and economic organization which is established on August 8, 1967. The objectives of the establishment of ASEAN include accelerating the economic growth and the social progress of cultural and social in Southeast Asia area. it is known that the income of ASEAN + 3 member countries is still very unbalanced with the index rate of an average of 0.98 per year. However, when it is viewed from year to year during the estimation period, the value of the Williamson Index tends to decrease, although it is very low. This shows the tendency of the movement of economic growth is increasingly convergent with the decreasing inequality level. The results of the analysis through calculation of Williamson Index are also in accordance with the results of the analysis conducted by panel data method. The result of panel data analysis shows that there is conditional and unconditional convergence process of economic growth of ASEAN + 3 countries because the dependent variable lag coefficient of -0.1 and -0.2 is between -1 and 0.
Keywords: Developing Country, Gross Domestic Product, Income, economic growth
