diff --git a/src/main/kotlin/app/termora/transport/FileTransportTableModel.kt b/src/main/kotlin/app/termora/transport/FileTransportTableModel.kt
index 93b1ce0..2ce9d36 100644
--- a/src/main/kotlin/app/termora/transport/FileTransportTableModel.kt
+++ b/src/main/kotlin/app/termora/transport/FileTransportTableModel.kt
@@ -81,7 +81,7 @@ class FileTransportTableModel(transportManager: TransportManager) : DefaultTable
             COLUMN_STATUS -> formatStatus(transport.state)
 
             // 如果进度已经完成但是状态还是传输中，那么进度显示：99%
-            COLUMN_PROGRESS -> String.format("%.0f%%", if (progress >= 100.0 && isTransporting) 99 else progress)
+            COLUMN_PROGRESS -> String.format("%.0f%%", if (progress >= 100.0 && isTransporting) 99.0 else progress)
 
             // 大小
             COLUMN_SIZE -> if (transport.size < 0) "-"
diff --git a/src/test/kotlin/app/termora/StringFormatTest.kt b/src/test/kotlin/app/termora/StringFormatTest.kt
new file mode 100644
index 0000000..bc74ee3
--- /dev/null
+++ b/src/test/kotlin/app/termora/StringFormatTest.kt
@@ -0,0 +1,14 @@
+package app.termora
+
+import org.junit.jupiter.api.assertDoesNotThrow
+import java.util.*
+import kotlin.test.Test
+import kotlin.test.assertFailsWith
+
+class StringFormatTest {
+    @Test
+    fun test() {
+        assertFailsWith(IllegalFormatConversionException::class) { String.format("%.0f%%", 99) }
+        assertDoesNotThrow { String.format("%.0f%%", 99.0) }
+    }
+}
\ No newline at end of file