diff --git a/src/main/java/gov/usgs/earthquake/nshmp/gmm/GmmInput.java b/src/main/java/gov/usgs/earthquake/nshmp/gmm/GmmInput.java
index 3141d2d264104f6c311021a684c3a407adfaccd1..43a0cd457820e487c53e71ec9183b533f021adab 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/gmm/GmmInput.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/gmm/GmmInput.java
@@ -732,7 +732,7 @@ public class GmmInput {
       Builder setDistances(double r) {
         set(RJB, Range.closed(0.0, r));
         set(RRUP, Range.closed(0.0, r));
-        set(RX, Range.closed(0.0, r));
+        set(RX, Range.closed(-r, r));
         return this;
       }