Evolution of the normalized LIRG fraction with redshift in three redshift bins up to z = 1. Open triangles: all LIRGs; filled circles: LIRGs in high-density environment (Σ ₁₀>90); open circles: LIRGs in low-density environment (Σ ₁₀ = 5–10, slightly shifted for clarity); solid line: expected evolution from the Magnelli et al. (2009) LF and the Ilbert et al. (2010) MF. The fractions are normalized to the value at z = 0.3–0.6.