Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/HydraRingVariable.cs
===================================================================
diff -u -rb600ee186729ba8742b05408fbb2101f33f200ee -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/HydraRingVariable.cs	(.../HydraRingVariable.cs)	(revision b600ee186729ba8742b05408fbb2101f33f200ee)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/HydraRingVariable.cs	(.../HydraRingVariable.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -26,9 +26,6 @@
     /// </summary>
     public abstract class HydraRingVariable
     {
-        private const double defaultHydraRingValue = 0.0;
-        private readonly double? defaultHydraRingNullValue = null;
-
         private readonly int variableId;
 
         /// <summary>
@@ -58,7 +55,7 @@
         {
             get
             {
-                return defaultHydraRingValue;
+                return double.NaN;
             }
         }
 
@@ -68,7 +65,7 @@
         public abstract HydraRingDistributionType DistributionType { get; }
 
         /// <summary>
-        /// Gets the deviation type of the variable..
+        /// Gets the deviation type of the variable.
         /// </summary>
         public abstract HydraRingDeviationType DeviationType { get; }
 
@@ -79,40 +76,40 @@
         {
             get
             {
-                return defaultHydraRingValue;
+                return double.NaN;
             }
         }
 
         /// <summary>
         /// Gets the parameter 2 value in case the variable is random.
         /// </summary>
-        public virtual double? Parameter2
+        public virtual double Parameter2
         {
             get
             {
-                return defaultHydraRingNullValue;
+                return double.NaN;
             }
         }
 
         /// <summary>
         /// Gets the parameter 3 value in case the variable is random.
         /// </summary>
-        public virtual double? Parameter3
+        public virtual double Parameter3
         {
             get
             {
-                return defaultHydraRingNullValue;
+                return double.NaN;
             }
         }
 
         /// <summary>
         /// Gets the parameter 4 value in case the variable is random.
         /// </summary>
-        public virtual double? Parameter4
+        public virtual double Parameter4
         {
             get
             {
-                return defaultHydraRingNullValue;
+                return double.NaN;
             }
         }
 
@@ -123,7 +120,7 @@
         {
             get
             {
-                return defaultHydraRingValue;
+                return double.NaN;
             }
         }
     }
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/LogNormalHydraRingVariable.cs
===================================================================
diff -u -r69ae0d0b75f56831b0058a4fcac37442a998e84e -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/LogNormalHydraRingVariable.cs	(.../LogNormalHydraRingVariable.cs)	(revision 69ae0d0b75f56831b0058a4fcac37442a998e84e)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/LogNormalHydraRingVariable.cs	(.../LogNormalHydraRingVariable.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -43,7 +43,7 @@
             this.shift = shift;
         }
 
-        public override double? Parameter3
+        public override double Parameter3
         {
             get
             {
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/RandomHydraRingVariable.cs
===================================================================
diff -u -rb600ee186729ba8742b05408fbb2101f33f200ee -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/RandomHydraRingVariable.cs	(.../RandomHydraRingVariable.cs)	(revision b600ee186729ba8742b05408fbb2101f33f200ee)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/RandomHydraRingVariable.cs	(.../RandomHydraRingVariable.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -53,7 +53,7 @@
             }
         }
 
-        public override double? Parameter2
+        public override double Parameter2
         {
             get
             {
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/TruncatedNormalHydraRingVariable.cs
===================================================================
diff -u -r69ae0d0b75f56831b0058a4fcac37442a998e84e -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/TruncatedNormalHydraRingVariable.cs	(.../TruncatedNormalHydraRingVariable.cs)	(revision 69ae0d0b75f56831b0058a4fcac37442a998e84e)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Data/Variables/TruncatedNormalHydraRingVariable.cs	(.../TruncatedNormalHydraRingVariable.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -46,15 +46,15 @@
             this.upperBoundary = upperBoundary;
         }
 
-        public override double? Parameter3
+        public override double Parameter3
         {
             get
             {
                 return lowerBoundary;
             }
         }
 
-        public override double? Parameter4
+        public override double Parameter4
         {
             get
             {
Index: Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Services/HydraRingConfigurationService.cs
===================================================================
diff -u -r92ce01ec6a2ac8d64f77a2a618c6b6e410a78812 -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Services/HydraRingConfigurationService.cs	(.../HydraRingConfigurationService.cs)	(revision 92ce01ec6a2ac8d64f77a2a618c6b6e410a78812)
+++ Ringtoets/HydraRing/src/Ringtoets.HydraRing.Calculation/Services/HydraRingConfigurationService.cs	(.../HydraRingConfigurationService.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -434,22 +434,22 @@
                             "DistributionType", (int?) hydraRingVariable.DistributionType
                         },
                         {
-                            "Parameter1", hydraRingVariable.Parameter1
+                            "Parameter1", GetHydraRingValue(hydraRingVariable.Parameter1)
                         },
                         {
-                            "Parameter2", hydraRingVariable.Parameter2
+                            "Parameter2", GetHydraRingNullableValue(hydraRingVariable.Parameter2)
                         },
                         {
-                            "Parameter3", hydraRingVariable.Parameter3
+                            "Parameter3", GetHydraRingNullableValue(hydraRingVariable.Parameter3)
                         },
                         {
-                            "Parameter4", hydraRingVariable.Parameter4
+                            "Parameter4", GetHydraRingNullableValue(hydraRingVariable.Parameter4)
                         },
                         {
                             "DeviationType", (int?) hydraRingVariable.DeviationType
                         },
                         {
-                            "CoefficientOfVariation", hydraRingVariable.CoefficientOfVariation
+                            "CoefficientOfVariation", GetHydraRingValue(hydraRingVariable.CoefficientOfVariation)
                         },
                         {
                             "CorrelationLength", GetHydraRingValue(variableDefaults.CorrelationLength)
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/DeterministicHydraRingVariableTest.cs
===================================================================
diff -u -r92ce01ec6a2ac8d64f77a2a618c6b6e410a78812 -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/DeterministicHydraRingVariableTest.cs	(.../DeterministicHydraRingVariableTest.cs)	(revision 92ce01ec6a2ac8d64f77a2a618c6b6e410a78812)
+++ Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/DeterministicHydraRingVariableTest.cs	(.../DeterministicHydraRingVariableTest.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -40,11 +40,11 @@
             Assert.AreEqual(2.2, hydraRingVariable.Value);
             Assert.AreEqual(HydraRingDistributionType.Deterministic, hydraRingVariable.DistributionType);
             Assert.AreEqual(HydraRingDeviationType.Standard, hydraRingVariable.DeviationType);
-            Assert.AreEqual(0, hydraRingVariable.Parameter1);
-            Assert.IsNull(hydraRingVariable.Parameter2);
-            Assert.IsNull(hydraRingVariable.Parameter3);
-            Assert.IsNull(hydraRingVariable.Parameter4);
-            Assert.AreEqual(0, hydraRingVariable.CoefficientOfVariation);
+            Assert.IsNaN(hydraRingVariable.Parameter1);
+            Assert.IsNaN(hydraRingVariable.Parameter2);
+            Assert.IsNaN(hydraRingVariable.Parameter3);
+            Assert.IsNaN(hydraRingVariable.Parameter4);
+            Assert.IsNaN(hydraRingVariable.CoefficientOfVariation);
         }
     }
 }
\ No newline at end of file
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/HydraRingVariableTest.cs
===================================================================
diff -u -rb600ee186729ba8742b05408fbb2101f33f200ee -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/HydraRingVariableTest.cs	(.../HydraRingVariableTest.cs)	(revision b600ee186729ba8742b05408fbb2101f33f200ee)
+++ Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/HydraRingVariableTest.cs	(.../HydraRingVariableTest.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -36,12 +36,12 @@
 
             // Assert
             Assert.AreEqual(1, hydraRingVariable.VariableId);
-            Assert.AreEqual(0, hydraRingVariable.Value);
-            Assert.AreEqual(0, hydraRingVariable.Parameter1);
-            Assert.IsNull(hydraRingVariable.Parameter2);
-            Assert.IsNull(hydraRingVariable.Parameter3);
-            Assert.IsNull(hydraRingVariable.Parameter4);
-            Assert.AreEqual(0, hydraRingVariable.CoefficientOfVariation);
+            Assert.IsNaN(hydraRingVariable.Value);
+            Assert.IsNaN(hydraRingVariable.Parameter1);
+            Assert.IsNaN(hydraRingVariable.Parameter2);
+            Assert.IsNaN(hydraRingVariable.Parameter3);
+            Assert.IsNaN(hydraRingVariable.Parameter4);
+            Assert.IsNaN(hydraRingVariable.CoefficientOfVariation);
         }
 
         private class TestHydraRingVariable : HydraRingVariable
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/LogNormalHydraRingVariableTest.cs
===================================================================
diff -u -r69ae0d0b75f56831b0058a4fcac37442a998e84e -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/LogNormalHydraRingVariableTest.cs	(.../LogNormalHydraRingVariableTest.cs)	(revision 69ae0d0b75f56831b0058a4fcac37442a998e84e)
+++ Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/LogNormalHydraRingVariableTest.cs	(.../LogNormalHydraRingVariableTest.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -41,13 +41,13 @@
         }
 
         [Test]
-        public void Constructor_ShiftNotSet_Parameter3Null()
+        public void Constructor_ShiftNotSet_Parameter3NaN()
         {
             // Call
             var hydraRingVariable = new LogNormalHydraRingVariable(1, HydraRingDeviationType.Standard, 2.2, 3.3);
 
             // Assert
-            Assert.IsNull(hydraRingVariable.Parameter3);
+            Assert.IsNaN(hydraRingVariable.Parameter3);
         }
     }
 }
\ No newline at end of file
Index: Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/RandomHydraRingVariableTest.cs
===================================================================
diff -u -r69ae0d0b75f56831b0058a4fcac37442a998e84e -r8acfb6734b3968d7874de486e0d21a3ff647b583
--- Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/RandomHydraRingVariableTest.cs	(.../RandomHydraRingVariableTest.cs)	(revision 69ae0d0b75f56831b0058a4fcac37442a998e84e)
+++ Ringtoets/HydraRing/test/Ringtoets.HydraRing.Calculation.Test/Data/Variables/RandomHydraRingVariableTest.cs	(.../RandomHydraRingVariableTest.cs)	(revision 8acfb6734b3968d7874de486e0d21a3ff647b583)
@@ -29,22 +29,22 @@
     public class RandomHydraRingVariableTest
     {
         [Test]
-        [TestCase(HydraRingDeviationType.Standard, 3.3, 0)]
-        [TestCase(HydraRingDeviationType.Variation, null, 3.3)]
-        public void Constructor_ExpectedValues(HydraRingDeviationType deviationType, double? expectedParameter2, double expectedCoefficientOfVariation)
+        [TestCase(HydraRingDeviationType.Standard, 3.3, double.NaN)]
+        [TestCase(HydraRingDeviationType.Variation, double.NaN, 3.3)]
+        public void Constructor_ExpectedValues(HydraRingDeviationType deviationType, double expectedParameter2, double expectedCoefficientOfVariation)
         {
             // Call
             var hydraRingVariable = new TestRandomHydraRingVariable(1, deviationType, 2.2, 3.3);
 
             // Assert
             Assert.IsInstanceOf<HydraRingVariable>(hydraRingVariable);
             Assert.AreEqual(1, hydraRingVariable.VariableId);
-            Assert.AreEqual(0.0, hydraRingVariable.Value);
+            Assert.IsNaN(hydraRingVariable.Value);
             Assert.AreEqual(deviationType, hydraRingVariable.DeviationType);
             Assert.AreEqual(2.2, hydraRingVariable.Parameter1);
             Assert.AreEqual(expectedParameter2, hydraRingVariable.Parameter2);
-            Assert.IsNull(hydraRingVariable.Parameter3);
-            Assert.IsNull(hydraRingVariable.Parameter4);
+            Assert.IsNaN(hydraRingVariable.Parameter3);
+            Assert.IsNaN(hydraRingVariable.Parameter4);
             Assert.AreEqual(expectedCoefficientOfVariation, hydraRingVariable.CoefficientOfVariation);
         }