Thüringen Becken (The Thuringian Basin) is located in the central/northern part of the Thüringen state in central Germany. It is a very small and mature producing region, which only has four very mature producing fields left - Fahner Höhe, Kirchheilingen, Langensalza and Mühlhausen. All fields are operated by GDF Suez. No further development is expected on these fields. We have modelled the Thüringer Becken region as a whole from 1991 onwards, using individual field production profiles, but an overall opex per barrel methodology.