diff --git a/NEWS b/NEWS
index de7b40085..b6e17f3e2 100644
--- a/NEWS
+++ b/NEWS
@@ -15,6 +15,8 @@ New configuration options in taskwarrior 1.9.4
 
   - color.burndown.pending, color.burndown.started and color.burndown.done
     control the color of the burndown charts.
+  - burndown.bias, which is a tweakable control for the completion estimation
+    for the burndown charts, and is documented in taskrc(5).
 
 Newly deprecated features in taskwarrior 1.9.4
 
diff --git a/src/burndown.cpp b/src/burndown.cpp
index 1c4418ea2..c888d8c9c 100644
--- a/src/burndown.cpp
+++ b/src/burndown.cpp
@@ -28,6 +28,7 @@
 #include <sstream>
 #include <algorithm>
 #include <math.h>
+#include <string.h>
 
 #include <Context.h>
 #include <Date.h>
@@ -52,8 +53,8 @@ public:
 
 public:
   int offset;                    // from left of chart
-  std::string major;             // x-axis label, major (year/-/month)
-  std::string minor;             // x-axis label, minor (month/week/day)
+  std::string major_label;       // x-axis label, major (year/-/month)
+  std::string minor_label;       // x-axis label, minor (month/week/day)
   int pending;                   // Number of pending tasks in period
   int started;                   // Number of started tasks in period
   int done;                      // Number of done tasks in period
@@ -64,8 +65,8 @@ public:
 ////////////////////////////////////////////////////////////////////////////////
 Bar::Bar ()
 : offset (0)
-, major ("")
-, minor ("")
+, major_label ("")
+, minor_label ("")
 , pending (0)
 , started (0)
 , done (0)
@@ -86,8 +87,8 @@ Bar& Bar::operator= (const Bar& other)
   if (this != &other)
   {
     offset      = other.offset;
-    major       = other.major;
-    minor       = other.minor;
+    major_label = other.major_label;
+    minor_label = other.minor_label;
     pending     = other.pending;
     started     = other.started;
     done        = other.done;
@@ -474,7 +475,7 @@ std::string Chart::render ()
 
   std::sort (bars_in_sequence.begin (), bars_in_sequence.end ());
   std::vector <time_t>::iterator seq;
-  std::string major;
+  std::string major_label;
   for (seq = bars_in_sequence.begin (); seq != bars_in_sequence.end (); ++seq)
   {
     Bar bar = bars[*seq];
@@ -482,12 +483,12 @@ std::string Chart::render ()
     // If it fits within the allowed space.
     if (bar.offset < actual_bars)
     {
-      grid.replace (LOC (height - 5, max_label + 3 + ((actual_bars - bar.offset - 1) * 3)), bar.minor.length (), bar.minor);
+      grid.replace (LOC (height - 5, max_label + 3 + ((actual_bars - bar.offset - 1) * 3)), bar.minor_label.length (), bar.minor_label);
 
-      if (major != bar.major)
-        grid.replace (LOC (height - 4, max_label + 3 + ((actual_bars - bar.offset - 1) * 3)), bar.major.length (), bar.major);
+      if (major_label != bar.major_label)
+        grid.replace (LOC (height - 4, max_label + 3 + ((actual_bars - bar.offset - 1) * 3)), bar.major_label.length (), bar.major_label);
 
-      major = bar.major;
+      major_label = bar.major_label;
     }
   }
 
@@ -709,27 +710,27 @@ void Chart::generateBars ()
     case 'D': // month/day
       {
         std::string month = Date::monthName (cursor.month ());
-        bar.major = month.substr (0, 3);
+        bar.major_label = month.substr (0, 3);
 
         sprintf (str, "%02d", cursor.day ());
-        bar.minor = str;
+        bar.minor_label = str;
       }
       break;
 
     case 'W': // year/week
       sprintf (str, "%d", cursor.year ());
-      bar.major = str;
+      bar.major_label = str;
 
       sprintf (str, "%02d", cursor.weekOfYear (0));
-      bar.minor = str;
+      bar.minor_label = str;
       break;
 
     case 'M': // year/month
       sprintf (str, "%d", cursor.year ());
-      bar.major = str;
+      bar.major_label = str;
 
       sprintf (str, "%02d", cursor.month ());
-      bar.minor = str;
+      bar.minor_label = str;
       break;
     }
 
diff --git a/src/command.cpp b/src/command.cpp
index ebfd9075b..0d01725bf 100644
--- a/src/command.cpp
+++ b/src/command.cpp
@@ -891,11 +891,12 @@ int handleShow (std::string& outs)
     // Note that there is a leading and trailing space, to make it easier to
     // search for whole words.
     std::string recognized =
-      " annotations blanklines bulk calendar.details calendar.details.report "
-      "calendar.holidays calendar.legend color color.active color.due "
-      "color.due.today color.blocked color.overdue color.pri.H color.pri.L "
-      "color.pri.M color.pri.none color.recurring color.tagged color.footnote "
-      "color.header color.debug color.alternate color.calendar.today "
+      " annotations blanklines bulk burndown.bias calendar.details "
+      "calendar.details.report calendar.holidays calendar.legend color "
+      "color.active color.due color.due.today color.blocked color.burndown.done "
+      "color.burndown.pending color.burndown.started color.overdue color.pri.H "
+      "color.pri.L color.pri.M color.pri.none color.recurring color.tagged "
+      "color.footnote color.header color.debug color.alternate color.calendar.today "
       "color.calendar.due color.calendar.due.today color.calendar.overdue "
       "color.calendar.weekend color.calendar.holiday color.calendar.weeknumber "
       "color.summary.background color.summary.bar color.history.add "