diff --git a/share/openbr/plotting/plot_utils.R b/share/openbr/plotting/plot_utils.R
index 82a7f0c..514f9c3 100644
--- a/share/openbr/plotting/plot_utils.R
+++ b/share/openbr/plotting/plot_utils.R
@@ -9,7 +9,13 @@ library("grid")
 
 # Code to format FAR values
 far_names <- list('0.001'="FAR = 0.1%", '0.01'="FAR = 1%")
-far_labeller <- function(variable,value) { return(far_names[as.character(value)]) }
+far_labeller <- function(variable,value) {
+    if (as.character(value) %in% names(far_names)) {
+        return(far_names[as.character(value)])
+    } else {
+        return(as.character(value))
+    }
+}
 
 getScale <- function(mode, title, vals) {
     if      (vals > 12) return(do.call(paste("scale", mode, "discrete", sep="_"), list(title)))