diff --git a/src/vehicle.cpp b/src/vehicle.cpp
--- a/src/vehicle.cpp
+++ b/src/vehicle.cpp
@@ -58,7 +58,6 @@
 
 #define GEN_HASH(x, y) ((GB((y), 6, 6) << 6) + GB((x), 7, 6))
 
-VehicleID _vehicle_id_ctr_day;
 VehicleID _new_vehicle_id;
 uint16 _returned_refit_capacity;      ///< Stores the capacity after a refit operation.
 uint16 _returned_mail_refit_capacity; ///< Stores the mail capacity after a refit operation (Aircraft only).