diff --git a/projects/openttd_vs80.vcproj b/projects/openttd_vs80.vcproj
--- a/projects/openttd_vs80.vcproj
+++ b/projects/openttd_vs80.vcproj
@@ -1024,6 +1024,10 @@
 				>
 			</File>
 			<File
+				RelativePath=".\..\src\graph_gui.h"
+				>
+			</File>
+			<File
 				RelativePath=".\..\src\group.h"
 				>
 			</File>
diff --git a/projects/openttd_vs90.vcproj b/projects/openttd_vs90.vcproj
--- a/projects/openttd_vs90.vcproj
+++ b/projects/openttd_vs90.vcproj
@@ -1021,6 +1021,10 @@
 				>
 			</File>
 			<File
+				RelativePath=".\..\src\graph_gui.h"
+				>
+			</File>
+			<File
 				RelativePath=".\..\src\group.h"
 				>
 			</File>
diff --git a/source.list b/source.list
--- a/source.list
+++ b/source.list
@@ -165,6 +165,7 @@ genworld.h
 gfx_func.h
 gfx_type.h
 gfxinit.h
+graph_gui.h
 group.h
 group_gui.h
 group_type.h
diff --git a/src/graph_gui.cpp b/src/graph_gui.cpp
--- a/src/graph_gui.cpp
+++ b/src/graph_gui.cpp
@@ -11,7 +11,7 @@
 
 #include "stdafx.h"
 #include "openttd.h"
-#include "gui.h"
+#include "graph_gui.h"
 #include "window_gui.h"
 #include "company_base.h"
 #include "company_gui.h"
diff --git a/src/graph_gui.h b/src/graph_gui.h
new file mode 100644
--- /dev/null
+++ b/src/graph_gui.h
@@ -0,0 +1,24 @@
+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file graph_gui.h Graph GUI functions. */
+
+#ifndef GRAPH_GUI_H
+#define GRAPH_GUI_H
+
+void ShowOperatingProfitGraph();
+void ShowIncomeGraph();
+void ShowDeliveredCargoGraph();
+void ShowPerformanceHistoryGraph();
+void ShowCompanyValueGraph();
+void ShowCargoPaymentRates();
+void ShowCompanyLeagueTable();
+void ShowPerformanceRatingDetail();
+
+#endif /* GRAPH_GUI_H */
diff --git a/src/gui.h b/src/gui.h
--- a/src/gui.h
+++ b/src/gui.h
@@ -29,16 +29,6 @@ void ShowGameDifficulty();
 void ShowGameSettings();
 void DrawArrowButtons(int x, int y, Colours button_colour, byte state, bool clickable_left, bool clickable_right);
 
-/* graph_gui.cpp */
-void ShowOperatingProfitGraph();
-void ShowIncomeGraph();
-void ShowDeliveredCargoGraph();
-void ShowPerformanceHistoryGraph();
-void ShowCompanyValueGraph();
-void ShowCargoPaymentRates();
-void ShowCompanyLeagueTable();
-void ShowPerformanceRatingDetail();
-
 /* train_gui.cpp */
 void ShowOrdersWindow(const Vehicle *v);
 
diff --git a/src/toolbar_gui.cpp b/src/toolbar_gui.cpp
--- a/src/toolbar_gui.cpp
+++ b/src/toolbar_gui.cpp
@@ -42,6 +42,7 @@
 #include "widgets/dropdown_type.h"
 #include "company_base.h"
 #include "smallmap_gui.h"
+#include "graph_gui.h"
 
 #include "network/network.h"
 #include "network/network_gui.h"