ECO D61: Queen's Gambit Declined

ECO D61 is part of volume D — Closed & Semi-Closed Games. The Lichess chess-openings dataset files one named line under it. It is Queen's Gambit Declined: Orthodox Defense, Rubinstein Variation: 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 Be7 5. Bg5 O-O 6. e3 Nbd7 7. Qc2.

That position has come up in 111,754 Lichess games between players rated 1600 to 2500: White won 51.0%, 6.5% were drawn and Black won 42.4%.