diff --git a/README.md b/README.md
index 83af7694..91b8637d 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ Large number arithmetic in Swift.
 
 | Package | Swift | iOS  | iPadOS | Mac Catalyst | macOS | tvOS | watchOS |
 |:-------:|:-----:|:----:|:------:|:------------:|:-----:|:----:|:-------:|
-| 3.0.0   | 5.8   | 16.4 | 16.4   | 16.4         | 13.3  | 16.4 | 9.4     |
+| 4.0.0   | 5.8   | 16.4 | 16.4   | 16.4         | 13.3  | 16.4 | 9.4     |
 
 ## ANKCoreKit ([Sources][COR/S], [Tests][COR/T], [Benchmarks][COR/B])
 
diff --git a/Sources/ANKFullWidthKit/ANKFullWidth+Shifts.swift b/Sources/ANKFullWidthKit/ANKFullWidth+Shifts.swift
index aac9a596..687dcfbf 100644
--- a/Sources/ANKFullWidthKit/ANKFullWidth+Shifts.swift
+++ b/Sources/ANKFullWidthKit/ANKFullWidth+Shifts.swift
@@ -241,8 +241,8 @@ extension ANKFullWidth {
         let sign = UInt(repeating: self.isLessThanZero)
         //=--------------------------------------=
         var destination = self.startIndex
-        var word = self[words]
-        let edge = self.endIndex &- words
+        let edge = self.distance(from: words, to: self.endIndex)
+        var word = self[words] as UInt
         
         while destination < self.endIndex {
             let after  = self.index(after: destination)