diff --git a/src/columns/ColTypeDuration.cpp b/src/columns/ColTypeDuration.cpp
index c4f5d54f0..34a2f58a4 100644
--- a/src/columns/ColTypeDuration.cpp
+++ b/src/columns/ColTypeDuration.cpp
@@ -43,21 +43,6 @@ ColumnTypeDuration::ColumnTypeDuration ()
   _type = "duration";
 }
 
-////////////////////////////////////////////////////////////////////////////////
-// Set the minimum and maximum widths for the value.
-void ColumnTypeDuration::measure (Task& task, unsigned int& minimum, unsigned int& maximum)
-{
-}
-
-////////////////////////////////////////////////////////////////////////////////
-void ColumnTypeDuration::render (
-  std::vector <std::string>& lines,
-  Task& task,
-  int width,
-  Color& color)
-{
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 void ColumnTypeDuration::modify (Task& task, const std::string& value)
 {
diff --git a/src/columns/ColTypeDuration.h b/src/columns/ColTypeDuration.h
index e864eff97..d556a486c 100644
--- a/src/columns/ColTypeDuration.h
+++ b/src/columns/ColTypeDuration.h
@@ -27,18 +27,14 @@
 #ifndef INCLUDED_COLTYPEDURATION
 #define INCLUDED_COLTYPEDURATION
 
-#include <vector>
 #include <string>
 #include <Column.h>
-#include <Color.h>
 #include <Task.h>
 
 class ColumnTypeDuration : public Column
 {
 public:
   ColumnTypeDuration ();
-  virtual void measure (Task&, unsigned int&, unsigned int&);
-  virtual void render (std::vector <std::string>&, Task&, int, Color&);
   virtual void modify (Task&, const std::string&);
 };