diff --git a/src/MainWindow.cpp b/src/MainWindow.cpp
index 4f266eb7c..ac919108a 100644
--- a/src/MainWindow.cpp
+++ b/src/MainWindow.cpp
@@ -1071,7 +1071,7 @@ void MainWindow::generateWeeklySummary()
     }
     
     int zone_range = -1;
-    double *time_in_zone = NULL;
+    QVector<double> time_in_zone;
     int num_zones = -1;
     bool zones_ok = true;
 
@@ -1123,9 +1123,8 @@ void MainWindow::generateWeeklySummary()
 		if (zone_range == -1) {
 		    zone_range = item->zoneRange();
 		    num_zones = item->numZones();
-		    time_in_zone = new double[num_zones];
-		    for (int j = 0; j < num_zones; ++j)
-			time_in_zone[j] = 0;
+                    time_in_zone.clear();
+                    time_in_zone.resize(num_zones);
 		}
 		else if (item->zoneRange() != zone_range) {
 		    zones_ok = false;
@@ -1196,13 +1195,10 @@ void MainWindow::generateWeeklySummary()
         if (!zones_ok)
             summary += "Error: Week spans more than one zone range.";
         else {
-            summary += zones->summarize(zone_range, time_in_zone, num_zones);
+            summary += zones->summarize(zone_range, time_in_zone);
         }
     }
 
-    if (time_in_zone)
-        delete [] time_in_zone;
-
     summary += "</center>";
 
     delete weeklyDistance;
diff --git a/src/RideItem.cpp b/src/RideItem.cpp
index be6e1825a..e91c807a7 100644
--- a/src/RideItem.cpp
+++ b/src/RideItem.cpp
@@ -40,8 +40,6 @@ RideItem::RideItem(int type,
     setText(2, dateTime.toString("h:mm AP"));
     setTextAlignment(1, Qt::AlignRight);
     setTextAlignment(2, Qt::AlignRight);
-
-    time_in_zone = NULL;
 }
 
 RideItem::~RideItem()
@@ -215,9 +213,8 @@ RideItem::htmlSummary()
 	    ((num_zones = (*zones)->numZones(zone_range)) > 0)
 	    )
 	    {
-		time_in_zone = new double[num_zones];
-		for (int i = 0; i < num_zones; ++i)
-		    time_in_zone[i] = 0.0;
+		time_in_zone.clear();
+		time_in_zone.resize(num_zones);
 	    }
  
 	const RideMetricFactory &factory = RideMetricFactory::instance();
@@ -393,7 +390,7 @@ RideItem::htmlSummary()
 	
         if (num_zones > 0) {
             summary += "<h2>Power Zones</h2>";
-            summary += (*zones)->summarize(zone_range, time_in_zone, num_zones);
+            summary += (*zones)->summarize(zone_range, time_in_zone);
         }
 
         // TODO: Ergomo uses non-consecutive interval numbers.
diff --git a/src/RideItem.h b/src/RideItem.h
index ac5d846c4..723c5f303 100644
--- a/src/RideItem.h
+++ b/src/RideItem.h
@@ -29,7 +29,7 @@ class RideItem : public QTreeWidgetItem {
 
     protected:
 
-        double *time_in_zone;
+        QVector<double> time_in_zone;
 
     public:
 
diff --git a/src/Zones.cpp b/src/Zones.cpp
index dd8219d80..b5a7aff72 100644
--- a/src/Zones.cpp
+++ b/src/Zones.cpp
@@ -668,11 +668,11 @@ QList <QString> Zones::getZoneNames(int rnum) {
   return return_values;
   }
 
-QString Zones::summarize(int rnum, double *time_in_zone, int num_zones) const
+QString Zones::summarize(int rnum, QVector<double> &time_in_zone) const
 {
     assert(rnum < ranges.size());
     ZoneRange *range = ranges[rnum];
-    assert(num_zones == range->zones.size());
+    assert(time_in_zone.size() == range->zones.size());
     QString summary;
     if(range->cp > 0){
         summary += "<table align=\"center\" width=\"70%\" border=\"0\">";
@@ -689,7 +689,7 @@ QString Zones::summarize(int rnum, double *time_in_zone, int num_zones) const
     summary += "<td align=\"center\">High</td>";
     summary += "<td align=\"center\">Time</td>";
     summary += "</tr>";
-    for (int zone = 0; zone < num_zones; ++zone) {
+    for (int zone = 0; zone < time_in_zone.size(); ++zone) {
         if (time_in_zone[zone] > 0.0) {
             QString name, desc;
             int lo, hi;
diff --git a/src/Zones.h b/src/Zones.h
index b1e198e60..4500d15c4 100644
--- a/src/Zones.h
+++ b/src/Zones.h
@@ -85,7 +85,7 @@ class Zones : public QObject
         void zoneInfo(int range, int zone,
                       QString &name, QString &description,
                       int &low, int &high) const;
-        QString summarize(int rnum, double *time_in_zone, int num_zones) const;
+        QString summarize(int rnum, QVector<double> &time_in_zone) const;
         int getCP(int rnum) const;
         void setCP(int rnum, int cp);
 	QString getDefaultZoneName(int z);