diff --git a/runelite-client/src/main/java/net/runelite/client/plugins/fps/FpsDrawListener.java b/runelite-client/src/main/java/net/runelite/client/plugins/fps/FpsDrawListener.java
index 3fdd3f6925..b729a4ad9f 100644
--- a/runelite-client/src/main/java/net/runelite/client/plugins/fps/FpsDrawListener.java
+++ b/runelite-client/src/main/java/net/runelite/client/plugins/fps/FpsDrawListener.java
@@ -54,7 +54,7 @@ public class FpsDrawListener implements Runnable
 
 	// Working set
 	private long lastMillis = 0;
-	private long[] lastDelays = new long[SAMPLE_SIZE];
+	private final long[] lastDelays = new long[SAMPLE_SIZE];
 	private int lastDelayIndex = 0;
 	private long sleepDelay = 0;