diff --git a/components/tachart/demo/nan/Main.lfm b/components/tachart/demo/nan/Main.lfm
index e5049c3143..d22859dc95 100644
--- a/components/tachart/demo/nan/Main.lfm
+++ b/components/tachart/demo/nan/Main.lfm
@@ -41,6 +41,10 @@ object Form1: TForm1
       BarBrush.Color = clRed
       Source = lcs1
     end
+    object Chart1AreaSeries1: TAreaSeries
+      Active = False
+      Source = lcs1
+    end
     object Chart1PieSeries1: TPieSeries
       Active = False
       Source = lcs1
@@ -79,6 +83,7 @@ object Form1: TForm1
       Items.Strings = (
         'Line'
         'Bar'
+        'Area'
         'Pie'
       )
       OnClick = rgSeriesTypeClick
diff --git a/components/tachart/demo/nan/Main.pas b/components/tachart/demo/nan/Main.pas
index e39b034e05..d064327cc4 100644
--- a/components/tachart/demo/nan/Main.pas
+++ b/components/tachart/demo/nan/Main.pas
@@ -11,6 +11,7 @@ uses
 type
   TForm1 = class(TForm)
     Chart1: TChart;
+    Chart1AreaSeries1: TAreaSeries;
     Chart1BarSeries1: TBarSeries;
     Chart1LineSeries1: TLineSeries;
     Chart1PieSeries1: TPieSeries;
diff --git a/components/tachart/demo/nan/nandemo.lpi b/components/tachart/demo/nan/nandemo.lpi
index 86503ef1ea..eb95f4a510 100644
--- a/components/tachart/demo/nan/nandemo.lpi
+++ b/components/tachart/demo/nan/nandemo.lpi
@@ -64,6 +64,8 @@
     </SearchPaths>
     <Linking>
       <Debugging>
+        <GenerateDebugInfo Value="True"/>
+        <DebugInfoType Value="dsAuto"/>
         <UseExternalDbgSyms Value="True"/>
       </Debugging>
       <Options>
diff --git a/components/tachart/tacustomseries.pas b/components/tachart/tacustomseries.pas
index 33231b6539..40341fd6a2 100644
--- a/components/tachart/tacustomseries.pas
+++ b/components/tachart/tacustomseries.pas
@@ -212,6 +212,9 @@ type
     FUpBound: Integer;
     FUseReticule: Boolean;
 
+  strict protected
+    procedure UpdateGraphPoints(AIndex: Integer); overload; inline;
+    procedure UpdateGraphPoints(AIndex, ALo, AUp: Integer); overload;
   protected
     procedure AfterAdd; override;
     procedure AfterDrawPointer(
@@ -224,7 +227,6 @@ type
     function GetZeroLevel: Double; virtual;
     procedure PrepareGraphPoints(
       const AExtent: TDoubleRect; AFilterByExtent: Boolean);
-    procedure UpdateGraphPoints(AIndex: Integer);
     procedure UpdateMargins(ADrawer: IChartDrawer; var AMargins: TRect); override;
     procedure UpdateMinXRange;
 
@@ -1025,16 +1027,21 @@ begin
   UpdateParentChart;
 end;
 
-procedure TBasicPointSeries.UpdateGraphPoints(AIndex: Integer);
+procedure TBasicPointSeries.UpdateGraphPoints(AIndex, ALo, AUp: Integer);
 var
   i: Integer;
 begin
   if IsRotated then
-    for i := FLoBound to FUpBound do
-      FGraphPoints[i - FLoBound].X += AxisToGraphY(Source[i]^.YList[AIndex])
+    for i := ALo to AUp do
+      FGraphPoints[i - ALo].X += AxisToGraphY(Source[i]^.YList[AIndex])
   else
-    for i := FLoBound to FUpBound do
-      FGraphPoints[i - FLoBound].Y += AxisToGraphY(Source[i]^.YList[AIndex]);
+    for i := ALo to AUp do
+      FGraphPoints[i - ALo].Y += AxisToGraphY(Source[i]^.YList[AIndex]);
+end;
+
+procedure TBasicPointSeries.UpdateGraphPoints(AIndex: Integer);
+begin
+  UpdateGraphPoints(AIndex, FLoBound, FUpBound);
 end;
 
 procedure TBasicPointSeries.UpdateMargins(
diff --git a/components/tachart/taseries.pas b/components/tachart/taseries.pas
index a5df13dcf7..fbe3a994f5 100644
--- a/components/tachart/taseries.pas
+++ b/components/tachart/taseries.pas
@@ -1068,11 +1068,91 @@ var
   end;
 
 var
-  i, j, n2, numPrevPts: Integer;
-  a, b: TDoublePoint;
   ext, ext2: TDoubleRect;
-  z, z1, z2: Double;
   prevPts: TPointArray;
+
+  procedure DrawSegment(AStart, AEnd: Integer);
+  var
+    i, j, n2, numPrevPts: Integer;
+    a, b: TDoublePoint;
+    z, z1, z2: Double;
+  begin
+    numPts := 0;
+    numPrevPts := 0;
+
+    if UseZeroLevel then
+      z := AxisToGraphY(ZeroLevel)
+    else
+      z := IfThen(IsRotated, ext2.a.X, ext2.a.Y);
+    z1 := z;
+    z2 := z;
+
+    for j := 0 to Source.YCount - 1 do begin
+      if j > 0 then
+        UpdateGraphPoints(j - 1, AStart, AEnd);
+      numPts := 0;
+      a := ProjToRect(FGraphPoints[AStart], ext2);
+      PushPoint(ProjToLine(a, z1));
+      z1 := IfThen(IsRotated, a.X, a.Y);
+      for i := AStart to AEnd - 1 do begin
+        a := FGraphPoints[i];
+        b := FGraphPoints[i + 1];
+        case ConnectType of
+          ctLine: ;
+          ctStepXY:
+            if IsRotated then
+              b.X := a.X
+            else
+              b.Y := a.Y;
+          ctStepYX:
+            if IsRotated then
+              a.X := b.X
+            else
+              a.Y := b.Y;
+        end;
+        // Avoid integer overflow at extreme zoom levels.
+        if LineIntersectsRect(a, b, ext2) then begin
+          PushPoint(a);
+          PushPoint(b);
+        end
+        else begin
+          PushPoint(ProjToRect(a, ext2));
+          PushPoint(ProjToRect(b, ext2));
+        end;
+      end;
+      a := ProjToRect(FGraphPoints[AEnd], ext2);
+      PushPoint(ProjToLine(a, z2));
+      z2 := IfThen(IsRotated, a.X, a.Y);
+      n2 := numPts;
+
+      for i := 0 to numPrevPts - 1 do
+        PushPoint(prevPts[numPrevPts - i - 1]);
+      for i := 0 to n2 - 1 do
+        prevPts[i] := pts[i];
+      numPrevPts := n2;
+
+      ADrawer.Brush := AreaBrush;
+      ADrawer.Pen := AreaContourPen;
+      if Styles <> nil then
+        Styles.Apply(ADrawer, j);
+      if Depth > 0 then
+        // Rendering is incorrect when values cross zero level.
+        for i := 1 to n2 - 2 do
+          ADrawer.DrawLineDepth(pts[i], pts[i + 1], Depth);
+      ADrawer.Polygon(pts, 0, numPts);
+    end;
+    if AreaLinesPen.Style <> psClear then begin
+      ADrawer.Pen := AreaLinesPen;
+      for i := AStart + 1 to AEnd - 1 do begin
+        a := ProjToRect(FGraphPoints[i], ext2);
+        b := ProjToLine(a, z);
+        ADrawer.Line(ParentChart.GraphToImage(a), ParentChart.GraphToImage(b));
+      end;
+    end;
+  end;
+
+var
+  i, j: Integer;
 begin
   if IsEmpty then exit;
 
@@ -1086,77 +1166,17 @@ begin
 
   SetLength(pts, Length(FGraphPoints) * 4 + 4);
   SetLength(prevPts, Length(pts));
-  numPrevPts := 0;
-
-  if UseZeroLevel then
-    z := AxisToGraphY(ZeroLevel)
-  else
-    z := IfThen(IsRotated, ext2.a.X, ext2.a.Y);
-  z1 := z;
-  z2 := z;
-
-  for j := 0 to Source.YCount - 1 do begin
-    if j > 0 then
-      UpdateGraphPoints(j - 1);
-    numPts := 0;
-    a := ProjToRect(FGraphPoints[0], ext2);
-    PushPoint(ProjToLine(a, z1));
-    z1 := IfThen(IsRotated, a.X, a.Y);
-    for i := 0 to High(FGraphPoints) - 1 do begin
-      a := FGraphPoints[i];
-      b := FGraphPoints[i + 1];
-      case ConnectType of
-        ctLine: ;
-        ctStepXY:
-          if IsRotated then
-            b.X := a.X
-          else
-            b.Y := a.Y;
-        ctStepYX:
-          if IsRotated then
-            a.X := b.X
-          else
-            a.Y := b.Y;
-      end;
-      // Avoid integer overflow at extreme zoom levels.
-      if LineIntersectsRect(a, b, ext2) then begin
-        PushPoint(a);
-        PushPoint(b);
+  j := -1;
+  for i := 0 to High(FGraphPoints) do
+    if IsNan(FGraphPoints[i]) = (j >= 0) then
+      if j >= 0 then begin
+        DrawSegment(j, i - 1);
+        j := -1;
       end
-      else begin
-        PushPoint(ProjToRect(a, ext2));
-        PushPoint(ProjToRect(b, ext2));
-      end;
-    end;
-    a := ProjToRect(FGraphPoints[High(FGraphPoints)], ext2);
-    PushPoint(ProjToLine(a, z2));
-    z2 := IfThen(IsRotated, a.X, a.Y);
-    n2 := numPts;
-
-    for i := 0 to numPrevPts - 1 do
-      PushPoint(prevPts[numPrevPts - i - 1]);
-    for i := 0 to n2 - 1 do
-      prevPts[i] := pts[i];
-    numPrevPts := n2;
-
-    ADrawer.Brush := AreaBrush;
-    ADrawer.Pen := AreaContourPen;
-    if Styles <> nil then
-      Styles.Apply(ADrawer, j);
-    if Depth > 0 then
-      // Rendering is incorrect when values cross zero level.
-      for i := 1 to n2 - 2 do
-        ADrawer.DrawLineDepth(pts[i], pts[i + 1], Depth);
-    ADrawer.Polygon(pts, 0, numPts);
-  end;
-  if AreaLinesPen.Style <> psClear then begin
-    ADrawer.Pen := AreaLinesPen;
-    for i := 1 to High(FGraphPoints) - 1 do begin
-      a := ProjToRect(FGraphPoints[i], ext2);
-      b := ProjToLine(a, z);
-      ADrawer.Line(ParentChart.GraphToImage(a), ParentChart.GraphToImage(b));
-    end;
-  end;
+      else
+        j := i;
+  if j >= 0 then
+    DrawSegment(j, High(FGraphPoints));
   DrawLabels(ADrawer);
 end;