ln April 2016, Sigit Haryadi find a method which he calls as Haryadi Index, which combines two old formulas which one is the Herfindahl-Hirschman Index, which is commonly used to measure the level of competition and the Gini Index, which is still used to evaluate the level of equality income people. Sigit Haryadi initially thought that Haryadi Index can only be used in the science of law and sociology, appropriate application of the Herfindahl-Hirschman area and Gini Index. But it was ...