Thailand is a unitary state; the administrative services of the executive branch are divided into three levels by ''National Government Organisation Act, BE 2534'' (1991): central, provincial and local. Thailand is composed of 76 provinces (, changwat), which are first-level administrative divisions. There are also two specially governed districts: the capital Bangkok and Pattaya. Bangkok is at provincial level and thus often counted as a province. Each province is divided into districts (, amphoe) and the districts are further divided into sub-districts (, tambons). The name of each province's capital city (, mueang) is the same as that of the province. For example, the capital of Chiang Mai Province (''Changwat Chiang Mai'') is ''Mueang Chiang Mai'' or ''Chiang Mai''. All provincial governors and district chiefs, which are administrators of provinces and districts respectively, are appointed by the central government. Thailand's provinces are sometimes grouped into four to six regions, depending on the source.