Short-term statistics (STS) are important early indicators of economic activity. The statistics are obligatory for all EU countries and also serve as input to national accounts. In most countries, short-term Statistics are based on business surveys. However, in recent years a number of countries have gradually replaced their business surveys with business VAT registry data. An important question is whether these surveys and registries are representative of the populations and whether representativity is stable in time. We apply R-indicators and partial R-indicators to measure the representativity of both kinds of data sources. We find large differences between different months of the year and between the two data sources. We discuss dual frame approaches that optimize the accuracy of STS statistics.