Proportion of professional worker is based on Indonesia's classification of occupation (KBJI). Professional workers include those who work as an expert, consultant, researcher, doctor, or academia. The data are taken from labour force survey (Sakernas) from year 2007 to 2020 and are expressed in percentage form. For 2007 to 2012 series, the classification is based on classification of occupation (KJI) 2000, meanwhile for 2013 to 2020 series the classification is based on classification of occupation (KBJI) 2002. With regard to the difference of classification base, the percentage of professional worker in 2013 and above series tend to be higher than the previous series.