diff --git a/src/stylesheets/tei2html/utils/numbering.xsl b/src/stylesheets/tei2html/utils/numbering.xsl
index 60ee414..4d8b75e 100755
--- a/src/stylesheets/tei2html/utils/numbering.xsl
+++ b/src/stylesheets/tei2html/utils/numbering.xsl
@@ -184,11 +184,11 @@
     <xsl:variable name="chapter" select="ancestor-or-self::tei:div[@type = 'chapter']"/>
     <xsl:variable name="chapter_nr">
       <xsl:choose>
-        <xsl:when test="$index_html">
-          <xsl:value-of select="count($chapter/preceding-sibling::*) +1"/>
+        <xsl:when test="//tei:body//tei:div[@type='part']">
+          <xsl:value-of select="count($chapter/preceding-sibling::*)"/>
         </xsl:when>
         <xsl:otherwise>
-          <xsl:value-of select="count($chapter/preceding-sibling::*)"/>
+          <xsl:value-of select="count($chapter/preceding-sibling::*) + 1"/>
         </xsl:otherwise>
       </xsl:choose>
     </xsl:variable>
@@ -211,11 +211,11 @@
     <xsl:variable name="chapter" select="ancestor-or-self::tei:div[@type = 'chapter']"/>
     <xsl:variable name="chapter_nr">
       <xsl:choose>
-        <xsl:when test="$index_html">
-          <xsl:value-of select="count($chapter/preceding-sibling::*) +1"/>
+        <xsl:when test="//tei:body//tei:div[@type='part']">
+          <xsl:value-of select="count($chapter/preceding-sibling::*)"/>
         </xsl:when>
         <xsl:otherwise>
-          <xsl:value-of select="count($chapter/preceding-sibling::*)"/>
+          <xsl:value-of select="count($chapter/preceding-sibling::*) + 1"/>
         </xsl:otherwise>
       </xsl:choose>
     </xsl:variable>
@@ -238,11 +238,11 @@
         <xsl:variable name="chapter" select="ancestor-or-self::tei:div[@type = 'chapter']"/>
         <xsl:variable name="chapter_nr">
           <xsl:choose>
-            <xsl:when test="$index_html">
-              <xsl:value-of select="count($chapter/preceding-sibling::*) +1"/>
+            <xsl:when test="//tei:body//tei:div[@type='part']">
+              <xsl:value-of select="count($chapter/preceding-sibling::*)"/>
             </xsl:when>
             <xsl:otherwise>
-              <xsl:value-of select="count($chapter/preceding-sibling::*)"/>
+              <xsl:value-of select="count($chapter/preceding-sibling::*) + 1"/>
             </xsl:otherwise>
           </xsl:choose>
         </xsl:variable>