diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/ValleyFiller.java b/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/ValleyFiller.java
new file mode 100644
index 000000000..ebc3b6496
--- /dev/null
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/ValleyFiller.java
@@ -0,0 +1,46 @@
+/*
+ * This file is part of ###PROJECT_NAME###
+ *
+ * Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+ *                    Desenvolvemento Tecnolóxico de Galicia
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.navalplanner.business.planner.entities;
+
+/**
+ * It fills valleys in the discrete function represented by hours. A valley is
+ * the portion between two maximum points. Besides the last value must be the
+ * maximum for all the function
+ * @author Óscar González Fernández <ogonzalez@igalia.com>
+ */
+public class ValleyFiller {
+
+    private ValleyFiller() {
+    }
+
+    public static int[] fillValley(int... hours) {
+        int[] result = new int[hours.length];
+        int lastMaximum = Integer.MIN_VALUE;
+        int globalMaximum = hours[hours.length - 1];
+        for (int i = 0; i < hours.length; i++) {
+            if (hours[i] > lastMaximum) {
+                lastMaximum = hours[i];
+            }
+            result[i] = Math.min(lastMaximum, globalMaximum);
+        }
+        return result;
+    }
+
+}
diff --git a/navalplanner-business/src/test/java/org/navalplanner/business/test/planner/entities/ValleyFillerTest.java b/navalplanner-business/src/test/java/org/navalplanner/business/test/planner/entities/ValleyFillerTest.java
new file mode 100644
index 000000000..2f3e3a5bd
--- /dev/null
+++ b/navalplanner-business/src/test/java/org/navalplanner/business/test/planner/entities/ValleyFillerTest.java
@@ -0,0 +1,60 @@
+/*
+ * This file is part of ###PROJECT_NAME###
+ *
+ * Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+ *                    Desenvolvemento Tecnolóxico de Galicia
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.navalplanner.business.test.planner.entities;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertThat;
+
+import org.junit.Test;
+import org.navalplanner.business.planner.entities.ValleyFiller;
+
+/**
+ * @author Óscar González Fernández <ogonzalez@igalia.com>
+ *
+ */
+public class ValleyFillerTest {
+
+    @Test
+    public void ifIsMonotonicIncreasingDoesntDoAnything() {
+        int[] param = { 2, 4, 8 };
+        int[] result = ValleyFiller.fillValley(param);
+        assertThat(result, equalTo(param));
+    }
+
+    @Test
+    public void ifHasValleyItFillsIt() {
+        int[] result = ValleyFiller.fillValley(2, 4, 8, 5, 6, 10);
+        assertThat(result, equalTo(new int[] { 2, 4, 8, 8, 8, 10 }));
+    }
+
+    @Test
+    public void ifEndsInValleyEndsAtLastValue() {
+        int[] result = ValleyFiller.fillValley(2, 4, 8, 5, 6);
+        assertThat(result, equalTo(new int[] { 2, 4, 6, 6, 6 }));
+    }
+
+    @Test
+    public void ifHasSeveralValleysWorksOk() {
+        int[] result = ValleyFiller.fillValley(2, 4, 8, 5, 6, 7, 9, 8, 11);
+        int[] expectedResult = { 2, 4, 8, 8, 8, 8, 9, 9, 11 };
+        assertThat(result, equalTo(expectedResult));
+    }
+
+}