diff --git a/Tr/TrackMonitors/src/VertexCompare.cpp b/Tr/TrackMonitors/src/VertexCompare.cpp
index 948de750374b3117ca884d797a28931e71d69b88..9aaa5016ae5efdb00849e7d49c9a3624347ae34f 100644
--- a/Tr/TrackMonitors/src/VertexCompare.cpp
+++ b/Tr/TrackMonitors/src/VertexCompare.cpp
@@ -41,7 +41,13 @@ using VertexType = Vertices::value_type;
 namespace {
   constexpr auto ntrack_bins = std::array{ 3.5, 15.5, 30.5, 45.5, 58.5, 70.5 };
   std::string    formatHistoTitle( std::string_view title, std::size_t idx ) {
-    return fmt::format( "{}, ntracks > {} & {} <ntracks", title, ntrack_bins[idx], ntrack_bins[idx + 1] );
+    return ( idx < ntrack_bins.size() - 1 )
+                  ? fmt::format( "{}, ntracks > {} & {} <ntracks", title, ntrack_bins[idx], ntrack_bins[idx + 1] )
+                  : fmt::format( "{}, ntracks > {}", title, ntrack_bins[idx] );
+  }
+  std::string formatHistoName( std::string_view title, std::size_t idx ) {
+    return idx < ntrack_bins.size() - 1 ? fmt::format( "{}_Monitoring_ntracks_bin{}", title, idx )
+                                        : fmt::format( "{}_Monitoring_ntracks_overflow", title );
   }
 } // namespace
 
@@ -266,15 +272,15 @@ private:
 
     MonitoringHistos( const VertexCompare* owner )
         : m_histo_nTracksBins_dx{ owner,
-                                  []( size_t idx ) { return fmt::format( "dx_Monitoring_ntracks_bin{}", idx ); },
+                                  []( size_t idx ) { return formatHistoName( "dx", idx ); },
                                   []( size_t idx ) { return formatHistoTitle( "dx, mm", idx ); },
                                   { 50, -0.15, 0.15 } }
         , m_histo_nTracksBins_dy{ owner,
-                                  []( size_t idx ) { return fmt::format( "dy_Monitoring_ntracks_bin{}", idx ); },
+                                  []( size_t idx ) { return formatHistoName( "dy", idx ); },
                                   []( size_t idx ) { return formatHistoTitle( "dy, mm", idx ); },
                                   { 50, -0.15, 0.15 } }
         , m_histo_nTracksBins_dz{ owner,
-                                  []( size_t idx ) { return fmt::format( "dz_Monitoring_ntracks_bin{}", idx ); },
+                                  []( size_t idx ) { return formatHistoName( "dz", idx ); },
                                   []( size_t idx ) { return formatHistoTitle( "dz, mm", idx ); },
                                   { 50, -1.5, 1.5 } }
         , m_histo_pullx_Monitoring{ owner, "pullx_Monitoring", "pull x", { 20, -5, 5 } }