The index of turnover in industry describes development in the turnover of manufacturing enterprises. Turnover for the largest enterprises in their respective industries is described with the data collected with the sales inquiry while the data on sales obtained from the periodic tax return data are exploited to describe the turnover of other enterprises. Turnover is exclusive of value added tax. The index is calculated separately for turnover, domestic sales and export turnover. The calculation is based on estimation of change. Sums by industry are calculated from information on the enterprises with comparable data on turnover from both the examined month and the corresponding month of the previous year. These sums are used to calculate annual changes by industry. Calculation of the annual changes also takes into consideration enterprise openings and closures, as well as restructuring and change of activity. The annual changes thus obtained are used to raise the turnover index of the corresponding month of the previous year. The latest index figures may become slightly revised as the volume of data grows and enterprises report changes to their data. Due to supplementations the data will become updated in releases for over twelve months. The statistics and indices complied from the data are public under the proviso that no individual enterprise’s data can be identified from them.