This economic study presents and analyses newly collected real-time data for Swiss GDP. It extends existing data sets by covering annual and quarterly aggregate GDP values for a longer sample, with vintages starting in 1971 (annual) and 1983 (quarterly). The analysis comprises a graphical and statistical description of quarterly GDP releases and tests for unbiasedness and efficiency of the revisions. Overall, revisions can be large and substantial, and early releases tend to underestimate GDP growth. Yet statistical tests on unbiasedness provide only limited evidence for a statistically significant bias. Additional tests point at some degree of informational inefficiency for selected revisions, and show that absolute revisions neither improve nor deteriorate over time. Most findings are consistent with existing literature. However, a closer look at revisions during the mid-nineties, a period characterised by large revisions, shows that annual and benchmark revisions can affect quarterly revisions considerably (and thus the results above). In addition, this closer look illustrates the difficulties with interpreting the recent business cycle in the presence of revisions.