diff --git a/config.def.h b/config.def.h
index ed339ed..2b06f34 100644
--- a/config.def.h
+++ b/config.def.h
@@ -1,7 +1,7 @@
 /* See LICENSE file for copyright and license details. */
 
 /* how often to update the statusbar (min value == 1) */
-#define UPDATE_INTERVAL 1
+static const int update_interval = 1;
 
 /* text to show if no value can be retrieved */
 #define UNKNOWN_STR "n/a"
diff --git a/slstatus.c b/slstatus.c
index aa05cd1..228c19b 100644
--- a/slstatus.c
+++ b/slstatus.c
@@ -914,11 +914,11 @@ main(int argc, char *argv[])
 			XSync(dpy, False);
 		}
 
-		if ((UPDATE_INTERVAL - delay) <= 0) {
+		if ((update_interval - delay) <= 0) {
 			delay = 0;
 			continue;
 		} else {
-			sleep(UPDATE_INTERVAL - delay);
+			sleep(update_interval - delay);
 			delay = 0;
 		}
 	}