In direct communication, the source explained:

With the release of the annual estimate for the year 2017 by Statistics Austria on the 25th of Sep, we have also updated the quarterly distribution of the annual data accordingly. Meaning that both unadjusted and adjusted data series have been revised back to the beginning of the series.

[...] the unadjusted data should be held up fixed up to the 4th quarter of 2017 and only the current quarters should be subject to revisions (e.g. due to new / revised data inputs) in our regular releases (flash-estimates and the update in t+60).

With respect to the adjusted data, the data series undergo revisions with each release due to the methodology of the seasonal adjustment procedure. In general, the revisions are more in magnitude at the current edge of the series and fade out going back to the begin.

In response, we have synchronized our extract as follows. Properties are otherwise unchanged.

• Quarterly national accounts, 1995Q1 to 2018Q3
• Annual national accounts, 1995 to 2017

The series reside in the historical catalog (Austria » National Accounts) and include, for example:

• NALICFCUA.IAUT   = National Accounts: By Income - Consumption of fixed capital, (Bil. EUR)
• NALENAVUA.IAUT   = By Expenditure - Acquisitions less disposals of valuables, (Bil. EUR)
• NACSGVAFIUQ.IAUT = By Production - Gross value added - Financial and insurance activities [K], (Mil. 2010 EUR, NSA)
• NALSSOPUQ.IAUT   = By Production - Subsidies on products, (Mil. EUR, NSA)

Because catalog locations are subject to change, the upper-right search box on DataBuffet.com provides a "find in catalog" mode that accepts a mnemonic.