diff --git a/examples/cluster.c b/examples/cluster.c
index 84c2795..0023085 100644
--- a/examples/cluster.c
+++ b/examples/cluster.c
@@ -63,7 +63,7 @@ static void draw_tachometer(cairo_t *cr,
     cairo_set_font_size(cr, 24);
 
     cairo_set_source_rgb(cr, 1, 1, 1);
-    cairo_arc(cr, x, y, r, 0, 360 * (M_PI/180));
+    cairo_arc(cr, x, y, r, 0, 2*M_PI);
     cairo_stroke(cr);
 
     /*