diff --git a/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFRichTextString.java b/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFRichTextString.java
index 89568f0b5..c58795075 100644
--- a/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFRichTextString.java
+++ b/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFRichTextString.java
@@ -279,13 +279,12 @@ public class XSSFRichTextString implements RichTextString {
      * @return  the number of characters this format run covers
      */
     public int getLengthOfFormattingRun(int index) {
-        if(st.sizeOfRArray() == 0) return length();
-
-        for(int i = 0; i < st.sizeOfRArray(); i++){
-            CTRElt r = st.getRArray(i);
-            if(i == index) return r.getT().length();
+        if(st.sizeOfRArray() == 0 || index >= st.sizeOfRArray()) {
+            return -1;
         }
-        return -1;
+
+        CTRElt r = st.getRArray(index);
+        return r.getT().length();
     }
 
     /**
@@ -342,16 +341,17 @@ public class XSSFRichTextString implements RichTextString {
      * @return  A copy of the  font used or null if no formatting is applied to the specified text run.
      */
     public XSSFFont getFontOfFormattingRun(int index) {
-        if(st.sizeOfRArray() == 0) return null;
-
-        for(int i = 0; i < st.sizeOfRArray(); i++){
-            CTRElt r = st.getRArray(i);
-            if(i == index && r.getRPr() != null) {
-               XSSFFont fnt = new XSSFFont(toCTFont(r.getRPr()));
-               fnt.setThemesTable(getThemesTable());
-               return fnt;
-            }
+        if(st.sizeOfRArray() == 0 || index >= st.sizeOfRArray()) {
+            return null;
         }
+
+        CTRElt r = st.getRArray(index);
+        if(r.getRPr() != null) {
+           XSSFFont fnt = new XSSFFont(toCTFont(r.getRPr()));
+           fnt.setThemesTable(getThemesTable());
+           return fnt;
+        }
+
         return null;
     }
 
diff --git a/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFRichTextString.java b/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFRichTextString.java
index 6d053bea1..3daa570b9 100644
--- a/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFRichTextString.java
+++ b/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFRichTextString.java
@@ -400,18 +400,35 @@ public final class TestXSSFRichTextString extends TestCase {
         Row row = sheet.getRow(0);
 
         // verify the values to ensure future changes keep the returned information equal 
-        assertEquals(0, row.getCell(0).getRichStringCellValue().numFormattingRuns());
-        assertEquals(0, row.getCell(1).getRichStringCellValue().numFormattingRuns());
+        XSSFRichTextString rt = (XSSFRichTextString) row.getCell(0).getRichStringCellValue();
+        assertEquals(0, rt.numFormattingRuns());
+        assertNull(rt.getFontOfFormattingRun(0));
+        assertEquals(-1, rt.getLengthOfFormattingRun(0));
         
-        XSSFRichTextString rt = (XSSFRichTextString) row.getCell(2).getRichStringCellValue();
+        rt = (XSSFRichTextString) row.getCell(1).getRichStringCellValue();
+        assertEquals(0, row.getCell(1).getRichStringCellValue().numFormattingRuns());
+        assertNull(rt.getFontOfFormattingRun(1));
+        assertEquals(-1, rt.getLengthOfFormattingRun(1));
+               
+        rt = (XSSFRichTextString) row.getCell(2).getRichStringCellValue();
         assertEquals(2, rt.numFormattingRuns());
         assertNotNull(rt.getFontOfFormattingRun(0));
+        assertEquals(4, rt.getLengthOfFormattingRun(0));
+        
         assertNotNull(rt.getFontOfFormattingRun(1));
+        assertEquals(9, rt.getLengthOfFormattingRun(1));
+
+        assertNull(rt.getFontOfFormattingRun(2));
         
         rt = (XSSFRichTextString) row.getCell(3).getRichStringCellValue();
         assertEquals(3, rt.numFormattingRuns());
         assertNull(rt.getFontOfFormattingRun(0));
+        assertEquals(1, rt.getLengthOfFormattingRun(0));
+        
         assertNotNull(rt.getFontOfFormattingRun(1));
+        assertEquals(3, rt.getLengthOfFormattingRun(1));
+        
         assertNotNull(rt.getFontOfFormattingRun(2));
+        assertEquals(9, rt.getLengthOfFormattingRun(2));
     }
 }