diff --git a/src/core/optimizer_stats.jl b/src/core/optimizer_stats.jl
index 19475381c6..dfac5c3cce 100644
--- a/src/core/optimizer_stats.jl
+++ b/src/core/optimizer_stats.jl
@@ -10,6 +10,7 @@ mutable struct OptimizerStats
     has_duals::Bool
     # Candidate solution
     objective_bound::Union{Missing, Float64}
+    relative_gap::Union{Missing, Float64}
     # Use missing instead of nothing so that CSV writting doesn't fail
     dual_objective_value::Union{Missing, Float64}
     # Work counters
@@ -37,6 +38,7 @@ function OptimizerStats()
         false,
         missing,
         missing,
+        missing,
         NaN,
         missing,
         missing,