The euro short-term rate (€STR) reflects the wholesale euro unsecured overnight borrowing costs of banks located in the euro area. The ECB publishes on its website the €STR at 08:00 CET on each TARGET2 business date. The €STR time series is updated on the ECB Data Portal (EDP) shortly after the €STR publication. The daily €STR is based on the transactions with overnight maturity that were traded and settled on the previous TARGET2 date. In EDP, the €STR series are indexed by time, where the time index reflects the trade date of the underlying transactions. For example, the observations on the rate, volume traded, etc. with time index 1 October 2019 reflect trading activity on that day, and correspond to the €STR published on 2 October 2019. For further information refer to the Overview of €STR. The ECB identified a need for preliminary figures, called pre-€STR , to be published prior to the full release of the €STR in October 2019. The pre-€STR was for information purposes only and not intended as a benchmark or reference rate. Pre-€STR series in the EDP The compounded €STR average rates and the compounded €STR index are updated in EDP shortly after their publication at 09:15 a.m. every TARGET2 business date. In EDP, all compounded €STR series are presented with a time index that reflects their reference date, which by convention coincides with end date of the related interest rate period underlying their calculation. For further information please refer to the Compounded €STR section of the overview of €STR webpage.