ECO E55: Nimzo-Indian Defense

ECO E55 is part of volume E — Indian Defenses. The Lichess chess-openings dataset files one named line under it. It is Nimzo-Indian Defense: Normal Variation, Gligoric System, Bronstein Variation: 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Bd3 d5 6. Nf3 c5 7. O-O dxc4 8. Bxc4 Nbd7.

That position has come up in 6,523 Lichess games between players rated 1600 to 2500: White won 44.0%, 6.3% were drawn and Black won 49.6%.