diff --git a/tests/Strata.SqlTools.SqlBreakdown.Tests/ExpressionTests/ExpressionFactoryFilterTests.cs b/tests/Strata.SqlTools.SqlBreakdown.Tests/ExpressionTests/ExpressionFactoryFilterTests.cs
index 25ce2f1..1fed843 100644
--- a/tests/Strata.SqlTools.SqlBreakdown.Tests/ExpressionTests/ExpressionFactoryFilterTests.cs
+++ b/tests/Strata.SqlTools.SqlBreakdown.Tests/ExpressionTests/ExpressionFactoryFilterTests.cs
@@ -6,6 +6,8 @@ namespace Strata.SqlTools.SqlBreakdown.Tests.ExpressionTests;
 public class ExpressionFactoryFilterTests : ExpressionTestsBase
 {
     private static readonly string[] values = new[] { "FY2019", "FY2020", "FY2021", "FY2022" };
+    private static readonly string[] monthListValues = new[] { "01-2020" };
+    private static readonly string[] calendarRange = new[] { "01/01/2019", "01/01/2023" };
 
     private static IEnumerable<TestCaseData> FilterTestCases()
     {
@@ -23,12 +25,12 @@ public class ExpressionFactoryFilterTests : ExpressionTestsBase
         ).SetName("DateListFilterFiscalYear_{m}");
 
         yield return new TestCaseData(
-            new Filter(4, FilterType.List, new[] { "01-2020" }, Array.Empty<FilterCondition>(), DatePart.Month, false, 0, 0),
+            new Filter(4, FilterType.List, monthListValues, Array.Empty<FilterCondition>(), DatePart.Month, false, 0, 0),
             "DEPT.DISCHARGE_DATE >= '2020-01-01' AND DEPT.DISCHARGE_DATE < '2020-02-01'"
         ).SetName("MonthListFilter_{m}");
 
         yield return new TestCaseData(
-            new Filter(4, FilterType.Calendar, new[] { "01/01/2019", "01/01/2023" }, Array.Empty<FilterCondition>(), DatePart.Month, false, 0, 0),
+            new Filter(4, FilterType.Calendar, calendarRange, Array.Empty<FilterCondition>(), DatePart.Month, false, 0, 0),
             "DEPT.DISCHARGE_DATE >= '2019-01-01' AND DEPT.DISCHARGE_DATE < '2023-01-01'"
         ).SetName("CalendarFilter_{m}");