diff --git a/.swift-version b/.swift-version
deleted file mode 100644
index 0062ac9..0000000
--- a/.swift-version
+++ /dev/null
@@ -1 +0,0 @@
-5.0.0
diff --git a/Static.podspec b/Static.podspec
index fd15dbf..a33d0ca 100644
--- a/Static.podspec
+++ b/Static.podspec
@@ -9,6 +9,7 @@ Pod::Spec.new do |spec|
   spec.author = { 'Venmo' => 'ios@venmo.com', 'Sam Soffes' => 'sam@soff.es' }
 
   spec.platform = :ios, '8.0'
+  spec.swift_version = '5.0'
   spec.frameworks = 'UIKit'
   spec.source_files = 'Static/*.{swift,h}'
 end
diff --git a/Static.xcodeproj/project.pbxproj b/Static.xcodeproj/project.pbxproj
index 1f19afb..d082f8c 100644
--- a/Static.xcodeproj/project.pbxproj
+++ b/Static.xcodeproj/project.pbxproj
@@ -49,6 +49,13 @@
 			remoteGlobalIDString = 21826AA91B3F51A100AA9641;
 			remoteInfo = "Static-iOS";
 		};
+		3B1129252226E5D800B6E06A /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = 21826AA11B3F51A100AA9641 /* Project object */;
+			proxyType = 1;
+			remoteGlobalIDString = 36748D4E1B5034EC0046F207;
+			remoteInfo = Example;
+		};
 /* End PBXContainerItemProxy section */
 
 /* Begin PBXCopyFilesBuildPhase section */
@@ -242,6 +249,7 @@
 			);
 			dependencies = (
 				21826AB71B3F51A100AA9641 /* PBXTargetDependency */,
+				3B1129262226E5D800B6E06A /* PBXTargetDependency */,
 			);
 			name = StaticTests;
 			productName = StaticTests;
@@ -391,6 +399,11 @@
 			target = 21826AA91B3F51A100AA9641 /* Static-iOS */;
 			targetProxy = 363129C51B50354E0024E339 /* PBXContainerItemProxy */;
 		};
+		3B1129262226E5D800B6E06A /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			target = 36748D4E1B5034EC0046F207 /* Example */;
+			targetProxy = 3B1129252226E5D800B6E06A /* PBXContainerItemProxy */;
+		};
 /* End PBXTargetDependency section */
 
 /* Begin PBXVariantGroup section */
diff --git a/Static.xcodeproj/xcshareddata/xcschemes/Example.xcscheme b/Static.xcodeproj/xcshareddata/xcschemes/Example.xcscheme
index 3c4e2b1..204b44d 100644
--- a/Static.xcodeproj/xcshareddata/xcschemes/Example.xcscheme
+++ b/Static.xcodeproj/xcshareddata/xcschemes/Example.xcscheme
@@ -28,6 +28,16 @@
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       shouldUseLaunchSchemeArgsEnv = "YES">
       <Testables>
+         <TestableReference
+            skipped = "NO">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "21826AB31B3F51A100AA9641"
+               BuildableName = "StaticTests.xctest"
+               BlueprintName = "StaticTests"
+               ReferencedContainer = "container:Static.xcodeproj">
+            </BuildableReference>
+         </TestableReference>
       </Testables>
       <MacroExpansion>
          <BuildableReference
diff --git a/Static/DataSource.swift b/Static/DataSource.swift
index 9e080a6..66107a7 100644
--- a/Static/DataSource.swift
+++ b/Static/DataSource.swift
@@ -28,7 +28,7 @@ public class DataSource: NSObject {
     public var sections: [Section] {
         didSet {
             assert(Thread.isMainThread, "You must access Static.DataSource from the main thread.")
-            refresh()
+            refresh(oldSections: oldValue)
         }
     }
 
@@ -101,8 +101,8 @@ public class DataSource: NSObject {
         refresh()
     }
 
-    private func refresh() {
-        refreshTableSections()
+    private func refresh(oldSections: [Section] = []) {
+        refreshTableSections(oldSections: oldSections)
         refreshRegisteredCells()
     }
 
@@ -127,9 +127,9 @@ public class DataSource: NSObject {
         return nil
     }
 
-    private func refreshTableSections(oldSections: [Section]? = nil) {
+    private func refreshTableSections(oldSections: [Section] = []) {
         guard let tableView = tableView else { return }
-        guard let oldSections = oldSections else {
+        guard !oldSections.isEmpty else {
             tableView.reloadData()
             return
         }
@@ -151,8 +151,7 @@ public class DataSource: NSObject {
                 tableView.insertSections(IndexSet(integersIn: range), with: animation)
             } else {
                 // Remove sections
-                let start = oldCount - 1
-                let range: Range<IndexSet.Element> = start..<(start - delta)
+                let range: Range<IndexSet.Element> = newCount..<(newCount - delta)
                 tableView.deleteSections(IndexSet(integersIn: range), with: animation)
             }
 
diff --git a/Static/Tests/DataSourceTests.swift b/Static/Tests/DataSourceTests.swift
index 67664f5..76b9a3a 100644
--- a/Static/Tests/DataSourceTests.swift
+++ b/Static/Tests/DataSourceTests.swift
@@ -41,6 +41,14 @@ class DataSourceTests: XCTestCase {
         XCTAssertEqual(4, tableView.numberOfRows(inSection: 1))
         XCTAssertEqual(2, tableView.numberOfRows(inSection: 2))
 
+        dataSource.sections = [
+            Section(rows: [Row(text: "Merrily"), Row(text: "Merrily")]),
+            Section(rows: [Row(text: "Life"), Row(text: "Is"), Row(text: "But"), Row(text: "A"), Row(text: "Dream")]),
+        ]
+        XCTAssertEqual(2, tableView.numberOfSections)
+        XCTAssertEqual(2, tableView.numberOfRows(inSection: 0))
+        XCTAssertEqual(5, tableView.numberOfRows(inSection: 1))
+
         dataSource.sections = []
         XCTAssertEqual(0, tableView.numberOfSections)
     }