diff --git a/libreplan-business/src/main/java/org/libreplan/business/orders/daos/SumChargedEffortDAO.java b/libreplan-business/src/main/java/org/libreplan/business/orders/daos/SumChargedEffortDAO.java
index babaab2cb..aad876f66 100644
--- a/libreplan-business/src/main/java/org/libreplan/business/orders/daos/SumChargedEffortDAO.java
+++ b/libreplan-business/src/main/java/org/libreplan/business/orders/daos/SumChargedEffortDAO.java
@@ -19,7 +19,11 @@
 
 package org.libreplan.business.orders.daos;
 
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Date;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 
@@ -149,9 +153,6 @@ public class SumChargedEffortDAO extends
     private void addDirectChargedEffort(OrderElement orderElement,
             EffortDuration effort) {
         SumChargedEffort sumChargedEffort = getByOrderElement(orderElement);
-        if (sumChargedEffort == null) {
-            sumChargedEffort = SumChargedEffort.create(orderElement);
-        }
 
         sumChargedEffort.addDirectChargedEffort(effort);
         save(sumChargedEffort);
@@ -163,9 +164,6 @@ public class SumChargedEffortDAO extends
             EffortDuration effort) {
         if (orderElement != null) {
             SumChargedEffort sumChargedEffort = getByOrderElement(orderElement);
-            if (sumChargedEffort == null) {
-                sumChargedEffort = SumChargedEffort.create(orderElement);
-            }
 
             sumChargedEffort.addIndirectChargedEffort(effort);
             save(sumChargedEffort);
@@ -231,6 +229,9 @@ public class SumChargedEffortDAO extends
                 .get(orderElement);
         if (sumChargedEffort == null) {
             sumChargedEffort = findByOrderElement(orderElement);
+            if (sumChargedEffort == null) {
+                sumChargedEffort = SumChargedEffort.create(orderElement);
+            }
             mapSumChargedEfforts.put(orderElement, sumChargedEffort);
         }
         return sumChargedEffort;
@@ -251,6 +252,7 @@ public class SumChargedEffortDAO extends
             resetMapSumChargedEfforts();
             resetSumChargedEffort(order);
             calculateDirectChargedEffort(order);
+            calculateFirstAndLastTimesheetDates(order);
         } catch (InstanceNotFoundException e) {
             throw new RuntimeException(e);
         }
@@ -258,9 +260,6 @@ public class SumChargedEffortDAO extends
 
     private void resetSumChargedEffort(OrderElement orderElement) {
         SumChargedEffort sumChargedEffort = getByOrderElement(orderElement);
-        if (sumChargedEffort == null) {
-            sumChargedEffort = SumChargedEffort.create(orderElement);
-        }
         sumChargedEffort.reset();
 
         for (OrderElement each : orderElement.getChildren()) {
@@ -281,4 +280,36 @@ public class SumChargedEffortDAO extends
         addDirectChargedEffort(orderElement, effort);
     }
 
+    private Pair<Date, Date> calculateFirstAndLastTimesheetDates(
+            OrderElement orderElement) {
+        Pair<Date, Date> minMax = workReportLineDAO
+                .findMinAndMaxDatesByOrderElement(orderElement);
+
+        Set<Date> minDates = new HashSet<Date>();
+        Set<Date> maxDates = new HashSet<Date>();
+
+        addIfNotNull(minDates, minMax.getFirst());
+        addIfNotNull(maxDates, minMax.getSecond());
+
+        for (OrderElement child : orderElement.getChildren()) {
+            Pair<Date, Date> minMaxChild = calculateFirstAndLastTimesheetDates(child);
+            addIfNotNull(minDates, minMaxChild.getFirst());
+            addIfNotNull(maxDates, minMaxChild.getSecond());
+        }
+
+        SumChargedEffort sumChargedEffort = getByOrderElement(orderElement);
+        sumChargedEffort.setTimesheetDates(minMax.getFirst(),
+                minMax.getSecond());
+
+        return Pair.create(
+                minDates.isEmpty() ? null : Collections.min(minDates),
+                maxDates.isEmpty() ? null : Collections.max(maxDates));
+    }
+
+    private void addIfNotNull(Collection<Date> list, Date date) {
+        if (date != null) {
+            list.add(date);
+        }
+    }
+
 }
diff --git a/libreplan-business/src/main/java/org/libreplan/business/orders/entities/SumChargedEffort.java b/libreplan-business/src/main/java/org/libreplan/business/orders/entities/SumChargedEffort.java
index fdd513247..b49ccb296 100644
--- a/libreplan-business/src/main/java/org/libreplan/business/orders/entities/SumChargedEffort.java
+++ b/libreplan-business/src/main/java/org/libreplan/business/orders/entities/SumChargedEffort.java
@@ -119,4 +119,10 @@ public class SumChargedEffort extends BaseEntity {
         this.lastTimesheetDate = lastTimesheetDate;
     }
 
+    public void setTimesheetDates(Date firstTimesheetDate,
+            Date lastTimesheetDate) {
+        setFirstTimesheetDate(firstTimesheetDate);
+        setLastTimesheetDate(lastTimesheetDate);
+    }
+
 }
diff --git a/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/IWorkReportLineDAO.java b/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/IWorkReportLineDAO.java
index 61b410c95..5af312036 100644
--- a/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/IWorkReportLineDAO.java
+++ b/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/IWorkReportLineDAO.java
@@ -28,6 +28,7 @@ import org.libreplan.business.common.daos.IIntegrationEntityDAO;
 import org.libreplan.business.orders.entities.OrderElement;
 import org.libreplan.business.reports.dtos.WorkReportLineDTO;
 import org.libreplan.business.resources.entities.Resource;
+import org.libreplan.business.util.Pair;
 import org.libreplan.business.workreports.entities.WorkReport;
 import org.libreplan.business.workreports.entities.WorkReportLine;
 
@@ -65,4 +66,7 @@ public interface IWorkReportLineDAO extends
     List<WorkReportLine> findByResourceFilteredByDateNotInWorkReport(
             Resource resource, Date start, Date end, WorkReport workReport);
 
+    Pair<Date, Date> findMinAndMaxDatesByOrderElement(
+            OrderElement orderElement);
+
 }
diff --git a/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/WorkReportLineDAO.java b/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/WorkReportLineDAO.java
index 4a40878d5..27036e0fc 100644
--- a/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/WorkReportLineDAO.java
+++ b/libreplan-business/src/main/java/org/libreplan/business/workreports/daos/WorkReportLineDAO.java
@@ -34,6 +34,7 @@ import org.libreplan.business.common.daos.IntegrationEntityDAO;
 import org.libreplan.business.orders.entities.OrderElement;
 import org.libreplan.business.reports.dtos.WorkReportLineDTO;
 import org.libreplan.business.resources.entities.Resource;
+import org.libreplan.business.util.Pair;
 import org.libreplan.business.workreports.entities.WorkReport;
 import org.libreplan.business.workreports.entities.WorkReportLine;
 import org.springframework.beans.factory.config.BeanDefinition;
@@ -146,4 +147,25 @@ public class WorkReportLineDAO extends IntegrationEntityDAO<WorkReportLine>
         return criteria.list();
     }
 
+    @Override
+    public Pair<Date, Date> findMinAndMaxDatesByOrderElement(
+            OrderElement orderElement) {
+
+        String strQuery = "SELECT MIN(date) AS min, MAX(date) AS max "
+                + "FROM WorkReportLine " + "WHERE orderElement = :orderElement";
+
+        Query query = getSession().createQuery(strQuery);
+        query.setParameter("orderElement", orderElement);
+
+        Object[] result = (Object[]) query.uniqueResult();
+
+        Date min = null;
+        Date max = null;
+        if (result != null) {
+            min = (Date) result[0];
+            max = (Date) result[1];
+        }
+        return Pair.create(min, max);
+    }
+
 }