Poland's current voivodeships (provinces) are largely based on the country's historic regions, whereas those of the past two decades (to 1998) had been centred on and named for individual cities. The new units range in area from less than  for Opole Voivodeship to more than  for Masovian Voivodeship. Administrative authority at the voivodeship level is shared between a government-appointed voivode (governor), an elected regional assembly (''sejmik'') and a voivodeship marshal, an executive elected by that assembly.