diff --git a/apps/calculation/additional_outputs/unit_list_controller.cpp b/apps/calculation/additional_outputs/unit_list_controller.cpp
index d43ece851..1f4cfe766 100644
--- a/apps/calculation/additional_outputs/unit_list_controller.cpp
+++ b/apps/calculation/additional_outputs/unit_list_controller.cpp
@@ -11,78 +11,101 @@ using namespace Poincare;
 
 namespace Calculation {
 
-int UnitListController::numberOfRows() const { //FIXME
-  return 2;
+void UnitListController::setExpression(Poincare::Expression e) {
+  // TODO: order of call issue!!!
+  ExpressionsListController::setExpression(e);
+  assert(!m_expression.isUninitialized());
+  // Reinitizlize m_memoizedExpressions
+  for (size_t i = 0; i < k_maxNumberOfCells; i++) {
+    m_memoizedExpressions[i] = Expression();
+  }
+
+  // 1. First result: SI units only
+  m_memoizedExpressions[0] = m_expression.clone();
+  Shared::PoincareHelpers::Simplify(&m_memoizedExpressions[0], App::app()->localContext(), ExpressionNode::ReductionTarget::User, Poincare::ExpressionNode::SymbolicComputation::ReplaceAllDefinedSymbolsWithDefinition, Poincare::ExpressionNode::UnitConversion::InternationalSystem);
+
+  // 2. Second result: miscellaneous classic units for some dimensions
+  ExpressionNode::ReductionContext reductionContext(
+      App::app()->localContext(),
+      Preferences::sharedPreferences()->complexFormat(),
+      Preferences::sharedPreferences()->angleUnit(),
+      ExpressionNode::ReductionTarget::User,
+      ExpressionNode::SymbolicComputation::ReplaceAllSymbolsWithDefinitionsOrUndefined);
+  Expression copy = m_expression.clone();
+  Expression units;
+  // Reduce to be able to recognize units
+  copy = copy.reduce(reductionContext);
+  copy = copy.removeUnit(&units);
+  bool requireSimplification = false;
+  bool canChangeUnitPrefix = false;
+  if (Unit::IsISSpeed(units)) {
+    // 2.a. Turn speed into km/h
+    m_memoizedExpressions[1] = UnitConvert::Builder(
+        m_expression.clone(),
+        Multiplication::Builder(
+          Unit::Kilometer(),
+          Power::Builder(
+            Unit::Hour(),
+            Rational::Builder(-1)
+            )
+          )
+        );
+    requireSimplification = true; // Reduce the conversion
+  } else if (Unit::IsISVolume(units)) {
+    // 2.b. Turn volume into L
+    m_memoizedExpressions[1] = UnitConvert::Builder(
+        m_expression.clone(),
+        Unit::Liter()
+        );
+    requireSimplification = true; // reduce the conversion
+    canChangeUnitPrefix = true; // Pick best prefix (mL)
+  } else if (Unit::IsISEnergy(units)) {
+    // 2.c. Turn energy into Wh
+    m_memoizedExpressions[1] = UnitConvert::Builder(
+        m_expression.clone(),
+        Multiplication::Builder(
+          Unit::Watt(),
+          Unit::Hour()
+          )
+        );
+    requireSimplification = true; // reduce the conversion
+    canChangeUnitPrefix = true; // Pick best prefix (kWh)
+  } else if (Unit::IsISTime(units)) {
+    // Turni time into ? year + ? month + ? day + ? h + ? min + ? s
+    double value = Shared::PoincareHelpers::ApproximateToScalar<double>(copy, App::app()->localContext());
+    m_memoizedExpressions[1] = Unit::BuildTimeSplit(value);
+  }
+  if (requireSimplification) {
+    Shared::PoincareHelpers::Simplify(&m_memoizedExpressions[1], App::app()->localContext(), ExpressionNode::ReductionTarget::User);
+  }
+  if (canChangeUnitPrefix) {
+    Expression newUnits;
+    m_memoizedExpressions[1] = m_memoizedExpressions[1].removeUnit(&newUnits);
+    double value = Shared::PoincareHelpers::ApproximateToScalar<double>(m_memoizedExpressions[1], App::app()->localContext());
+    Unit::ChooseBestMultipleForValue(&newUnits, &value, reductionContext);
+    m_memoizedExpressions[1] = Multiplication::Builder(Number::FloatNumber(value), newUnits);
+  }
+
+  if (!m_memoizedExpressions[1].isUninitialized() && m_memoizedExpressions[0].isIdenticalTo(m_memoizedExpressions[1])) {
+    // Avoid displaying duplicate
+    m_memoizedExpressions[1] = Expression();
+  }
+  // TODO m_memoizedExpressions[2]?
 }
 
-void UnitListController::computeLayoutAtIndex(int index) { //FIXME
-  Expression expressionAtIndex = m_expression.clone();
-  if (index == 0) {
-    // SI units only
-    Shared::PoincareHelpers::Simplify(&expressionAtIndex, App::app()->localContext(), ExpressionNode::ReductionTarget::User, Poincare::ExpressionNode::SymbolicComputation::ReplaceAllDefinedSymbolsWithDefinition, Poincare::ExpressionNode::UnitConversion::InternationalSystem);
-  } else if (index == 1) {
-    // Miscellaneous classic units for some dimensions
-    ExpressionNode::ReductionContext reductionContext(
-        App::app()->localContext(),
-        Preferences::sharedPreferences()->complexFormat(),
-        Preferences::sharedPreferences()->angleUnit(),
-        ExpressionNode::ReductionTarget::User,
-        ExpressionNode::SymbolicComputation::ReplaceAllSymbolsWithDefinitionsOrUndefined);
-    Expression units;
-    // Reduce to be able to recognize units
-    expressionAtIndex = expressionAtIndex.reduce(reductionContext);
-    expressionAtIndex = expressionAtIndex.removeUnit(&units);
-    bool requireSimplification = false;
-    bool canChangeUnitPrefix = false;
-    if (Unit::IsISSpeed(units)) {
-      // Turn into km/h
-      expressionAtIndex = UnitConvert::Builder(
-          m_expression.clone(),
-          Multiplication::Builder(
-            Unit::Kilometer(),
-            Power::Builder(
-              Unit::Hour(),
-              Rational::Builder(-1)
-              )
-            )
-          );
-      requireSimplification = true; // Reduce the conversion
-    } else if (Unit::IsISVolume(units)) {
-      // Turn into L
-      expressionAtIndex = UnitConvert::Builder(
-          m_expression.clone(),
-          Unit::Liter()
-          );
-      requireSimplification = true; // reduce the conversion
-      canChangeUnitPrefix = true; // Pick best prefix (mL)
-    } else if (Unit::IsISEnergy(units)) {
-      // Turn into W
-      expressionAtIndex = UnitConvert::Builder(
-          m_expression.clone(),
-          Multiplication::Builder(
-              Unit::Watt(),
-              Unit::Hour()
-            )
-          );
-      requireSimplification = true; // reduce the conversion
-      canChangeUnitPrefix = true; // Pick best prefix (kWh)
-    } else if (Unit::IsISTime(units)) {
-      // Turn into ? year + ? month + ? day + ? h + ? min + ? s
-      double value = Shared::PoincareHelpers::ApproximateToScalar<double>(expressionAtIndex, App::app()->localContext());
-      expressionAtIndex = Unit::BuildTimeSplit(value);
-    }
-    if (requireSimplification) {
-      Shared::PoincareHelpers::Simplify(&expressionAtIndex, App::app()->localContext(), ExpressionNode::ReductionTarget::User);
-    }
-    if (canChangeUnitPrefix) {
-      Expression newUnits;
-      expressionAtIndex = expressionAtIndex.removeUnit(&newUnits);
-      double value = Shared::PoincareHelpers::ApproximateToScalar<double>(expressionAtIndex, App::app()->localContext());
-      Unit::ChooseBestMultipleForValue(&newUnits, &value, reductionContext);
-      expressionAtIndex = Multiplication::Builder(Number::FloatNumber(value), newUnits);
+int UnitListController::numberOfRows() const {
+  int nbOfRows = 0;
+  for (size_t i = 0; i < k_maxNumberOfCells; i++) {
+    if (!m_memoizedExpressions[i].isUninitialized()) {
+      nbOfRows++;
     }
   }
-  m_layouts[index] = Shared::PoincareHelpers::CreateLayout(expressionAtIndex);
+  return nbOfRows;
+}
+
+void UnitListController::computeLayoutAtIndex(int index) {
+  assert(!m_memoizedExpressions[index].isUninitialized());
+  m_layouts[index] = Shared::PoincareHelpers::CreateLayout(m_memoizedExpressions[index]);
 }
 
 I18n::Message UnitListController::messageAtIndex(int index) {
diff --git a/apps/calculation/additional_outputs/unit_list_controller.h b/apps/calculation/additional_outputs/unit_list_controller.h
index 1e9d168bd..e3fdee036 100644
--- a/apps/calculation/additional_outputs/unit_list_controller.h
+++ b/apps/calculation/additional_outputs/unit_list_controller.h
@@ -10,11 +10,15 @@ public:
   UnitListController(EditExpressionController * editExpressionController) :
     ExpressionsListController(editExpressionController) {}
 
+  void setExpression(Poincare::Expression e) override;
+
   //ListViewDataSource
   int numberOfRows() const override;
 private:
   void computeLayoutAtIndex(int index) override;
   I18n::Message messageAtIndex(int index) override;
+  // Memoization of expressions
+  mutable Poincare::Expression m_memoizedExpressions[k_maxNumberOfCells];
 };
 
 }