ECO A87: Dutch Defense

ECO A87 is part of volume A — Flank Openings. The Lichess chess-openings dataset files one named line under it. It is Dutch Defense: Leningrad Variation: 1. d4 f5 2. c4 Nf6 3. g3 g6 4. Bg2 Bg7 5. Nf3.

That position has come up in 145,721 Lichess games between players rated 1600 to 2500: White won 49.3%, 6.5% were drawn and Black won 44.3%.