Index: Ringtoets/GrassCoverErosionOutwards/src/Ringtoets.GrassCoverErosionOutwards.Forms/PropertyClasses/GrassCoverErosionOutwardsWaveHeightLocationProperties.cs
===================================================================
diff -u -r0f28eb71a18af127ad376776ebd2cd597a0aa5c5 -r61ab2a112211952c337eea98bae62a4c93335229
--- Ringtoets/GrassCoverErosionOutwards/src/Ringtoets.GrassCoverErosionOutwards.Forms/PropertyClasses/GrassCoverErosionOutwardsWaveHeightLocationProperties.cs	(.../GrassCoverErosionOutwardsWaveHeightLocationProperties.cs)	(revision 0f28eb71a18af127ad376776ebd2cd597a0aa5c5)
+++ Ringtoets/GrassCoverErosionOutwards/src/Ringtoets.GrassCoverErosionOutwards.Forms/PropertyClasses/GrassCoverErosionOutwardsWaveHeightLocationProperties.cs	(.../GrassCoverErosionOutwardsWaveHeightLocationProperties.cs)	(revision 61ab2a112211952c337eea98bae62a4c93335229)
@@ -135,7 +135,8 @@
         {
             get
             {
-                return new EnumDisplayWrapper<CalculationConvergence>(data.WaveHeightCalculationConvergence).DisplayName;
+                CalculationConvergence convergence = data.WaveHeightCalculation.Output?.CalculationConvergence ?? CalculationConvergence.NotCalculated;
+                return new EnumDisplayWrapper<CalculationConvergence>(convergence).DisplayName;
             }
         }