diff --git a/src/DynamicModel.cc b/src/DynamicModel.cc
index 8418e8f23d251a7a0f7017df5610c963836028cc..ea98032b0542efed4f97d637d6140cbfffe2ac09 100644
--- a/src/DynamicModel.cc
+++ b/src/DynamicModel.cc
@@ -5150,7 +5150,7 @@ DynamicModel::computeDynJacobianCols(bool jacobianExo)
       int lag = it.first.second;
       int deriv_id = it.second;
       SymbolType type = symbol_table.getType(symb_id);
-      int tsid = symbol_table.getTypeSpecificID(symb_id);
+      int tsid = symbol_table.getTypeSpecificID(symb_id); // At this point, there is no trend_var
 
       switch (type)
         {
diff --git a/src/ParsingDriver.cc b/src/ParsingDriver.cc
index 8c15fd66661c6dd4a5ba8702505d013211689a05..0d6139fe9e4e1d9fec70e59b04a1714c1bfe896e 100644
--- a/src/ParsingDriver.cc
+++ b/src/ParsingDriver.cc
@@ -249,6 +249,10 @@ ParsingDriver::begin_trend()
 void
 ParsingDriver::declare_trend_var(bool log_trend, const string &name, const string &tex_name)
 {
+  /* Run detrending engine if trend variables are present, even if unused in
+     a var(deflator=…) statement (see #113). */
+  mod_file->nonstationary_variables = true;
+
   declare_symbol(name, log_trend ? SymbolType::logTrend : SymbolType::trend, tex_name, {});
   declared_trend_vars.push_back(mod_file->symbol_table.getID(name));
 }