diff --git a/Octokit.Tests/Octokit.Tests.csproj b/Octokit.Tests/Octokit.Tests.csproj
index 05307427..e93b79b9 100644
--- a/Octokit.Tests/Octokit.Tests.csproj
+++ b/Octokit.Tests/Octokit.Tests.csproj
@@ -145,6 +145,7 @@
     <Compile Include="Reactive\ObservableReleasesClientTests.cs" />
     <Compile Include="Reactive\ObservableRepositoriesClientTests.cs" />
     <Compile Include="Reactive\ObservableStarredClientTests.cs" />
+    <Compile Include="Reactive\ObservableStatisticsClientTests.cs" />
     <Compile Include="Reactive\ObservableTreesClientTests.cs" />
     <Compile Include="Reactive\ObservableFollowersTest.cs" />
     <Compile Include="Reactive\ObservableUserEmailsClientTests.cs" />
diff --git a/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs b/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs
index 35b1666d..c571bc65 100644
--- a/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs
+++ b/Octokit.Tests/Reactive/ObservableMilestonesClientTests.cs
@@ -3,7 +3,6 @@ using System.Collections.Generic;
 using System.Reactive.Linq;
 using System.Threading.Tasks;
 using NSubstitute;
-using Octokit;
 using Octokit.Internal;
 using Octokit.Reactive;
 using Octokit.Tests.Helpers;
diff --git a/Octokit.Tests/Reactive/ObservableStatisticsClientTests.cs b/Octokit.Tests/Reactive/ObservableStatisticsClientTests.cs
new file mode 100644
index 00000000..8bd6c2d0
--- /dev/null
+++ b/Octokit.Tests/Reactive/ObservableStatisticsClientTests.cs
@@ -0,0 +1,41 @@
+using System;
+using System.Reactive.Linq;
+using System.Threading.Tasks;
+using NSubstitute;
+using Octokit.Reactive;
+using Octokit.Tests.Helpers;
+using Xunit;
+
+namespace Octokit.Tests.Reactive
+{
+    public class ObservableStatisticsClientTests
+    {
+        public class TheGetMethod
+        {
+            [Fact]
+            public void GetsFromClientIssueMilestone()
+            {
+                var gitHubClient = Substitute.For<IGitHubClient>();
+                var statisticsClient = new ObservableStatisticsClient(gitHubClient);
+
+                statisticsClient.GetContributors("username", "repositoryName");
+
+                gitHubClient.Statistics.Received().GetContributors("username", "repositoryName");
+            }
+
+            [Fact]
+            public async Task ThrowsIfGivenNullRepositoryName()
+            {   
+                var statisticsClient = new ObservableStatisticsClient(Substitute.For<IGitHubClient>());
+                await AssertEx.Throws<ArgumentNullException>(async () => await statisticsClient.GetContributors("owner", null));
+            }
+
+            [Fact]
+            public async Task ThrowsIfGivenNullOwnerName()
+            {
+                var statisticsClient = new ObservableStatisticsClient(Substitute.For<IGitHubClient>());
+                await AssertEx.Throws<ArgumentNullException>(async () => await statisticsClient.GetContributors(null, "repositoryName"));
+            }
+        }
+    }
+}
\ No newline at end of file