diff --git a/src/main/java/org/neuroml/importer/sbml/SBMLImporter.java b/src/main/java/org/neuroml/importer/sbml/SBMLImporter.java
index 3c84cc4..5317e84 100644
--- a/src/main/java/org/neuroml/importer/sbml/SBMLImporter.java
+++ b/src/main/java/org/neuroml/importer/sbml/SBMLImporter.java
@@ -831,7 +831,7 @@ else if (r.isAssignment()) {
             E.info(">>>> StateVariable "+sv);
             dyn.stateVariables.add(sv);
 
-            TimeDerivative td = new TimeDerivative(sv.getName(), "1");
+            TimeDerivative td = new TimeDerivative(sv.getName(), timeScale.getName() + "* 1");
             dyn.timeDerivatives.add(td);
         }