diff --git a/contract/views/contract.xml b/contract/views/contract.xml
index 7b88d3146..ae422449d 100644
--- a/contract/views/contract.xml
+++ b/contract/views/contract.xml
@@ -473,6 +473,14 @@
                                     the
                                     invoiced period
                                 </p>
+                                <p colspan="2">
+                                    <strong
+                                    >#INVOICEMONTHNUMBER#</strong>: Invoice month number of the period
+                                </p>
+                                <p colspan="2">
+                                    <strong
+                                    >#INVOICEYEAR#</strong>: Invoice year of the period
+                                </p>
                             </group>
                         </page>
                     </notebook>