Survey questions may be added or dropped over time to better meet data users’ needs or to reduce the burden on survey respondents. The utility of survey questions, feedback from data users, and the burden on survey respondents are all considered in the survey question planning process.

In addition, typically every five years BEA conducts benchmark surveys (or censuses) on direct investment and trade in services. These surveys are the most comprehensive surveys in two respects: They collect data for the entire survey universe, and they typically include data items than are not collected in the other surveys.

To reduce the reporting burden on the U.S. companies that must file, reports are not required in quarterly and annual sample surveys for small affiliates and for services traders with small transactions. Instead, BEA estimates the data for these entities by extrapolating forward their data from the most recent benchmark survey based on the movement of the sample data. Thus, coverage of the universe is complete in non-benchmark periods, even though data is collected from fewer respondents. The benchmark surveys for direct investment are conducted in place of the annual survey on the activities of multinational enterprises, while the quarterly surveys on trade in services and direct investment are still collected in the year of the benchmark survey.