In order to speed up the processing of reports, a portion of data is used to extrapolate (or estimate) the complete set of data for the report. Sampling occurs when you request specific data in your reports when there are more than 500,000 sessions in the Properties are created within a Google Analytics account. Each property represents an instance of the tracking ID used to collect data from a website, group of websites, a mobile app or the Measurement Protocol. Each property will include data sent to the associated tracking ID. Once data has been collected it is processed in the reporting view (or views) created under the property. See also tracking ID.... Always-R Glossary for the selected date range. The easiest way to reduce sampling is to reduce the selected date range.