Complex sentence: For the 1987 population census, some 500 000 enumerators were required and for 2011, a change in methodology was planned, and the costs of the largely register-based census were expected to be only about one third of the expenditure of a traditional population census.
Split into simpler sentences: For the 1987 population census, some 500 000 enumerators were required. For 2011, a change in methodology is planned, and the costs of the largely register-based census are expected to be only about one third of the expenditure of a traditional population census.