diff --git a/src/Bundle/ChillPersonBundle/Export/Aggregator/AccompanyingCourseAggregators/DurationAggregator.php b/src/Bundle/ChillPersonBundle/Export/Aggregator/AccompanyingCourseAggregators/DurationAggregator.php
index 8d1960dda..0dc66e81e 100644
--- a/src/Bundle/ChillPersonBundle/Export/Aggregator/AccompanyingCourseAggregators/DurationAggregator.php
+++ b/src/Bundle/ChillPersonBundle/Export/Aggregator/AccompanyingCourseAggregators/DurationAggregator.php
@@ -13,21 +13,23 @@ namespace Chill\PersonBundle\Export\Aggregator\AccompanyingCourseAggregators;
 
 use Chill\MainBundle\Export\AggregatorInterface;
 use Chill\PersonBundle\Export\Declarations;
+use DateTimeImmutable;
 use Doctrine\ORM\QueryBuilder;
+use LogicException;
 use Symfony\Component\Form\Extension\Core\Type\ChoiceType;
 use Symfony\Component\Form\FormBuilderInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 final class DurationAggregator implements AggregatorInterface
 {
-    private TranslatorInterface $translator;
-
     private const CHOICES = [
         'month',
         'week',
-        'day'
+        'day',
     ];
 
+    private TranslatorInterface $translator;
+
     public function __construct(TranslatorInterface $translator)
     {
         $this->translator = $translator;
@@ -42,23 +44,29 @@ final class DurationAggregator implements AggregatorInterface
     {
         switch ($data['precision']) {
             case 'day':
-                $qb->addSelect('(COALESCE(acp.closingDate, NOW()) - acp.openingDate)  AS duration_aggregator');
+                $qb->addSelect('(COALESCE(acp.closingDate, :now) - acp.openingDate)  AS duration_aggregator');
+
                 break;
+
             case 'week':
-                $qb->addSelect('EXTRACT (YEAR FROM AGE(COALESCE(acp.closingDate, NOW()), acp.openingDate) * 52 +
-                    EXTRACT (WEEK FROM AGE(COALESCE(acp.closingDate, NOW()');
+                $qb->addSelect('(COALESCE(acp.closingDate, :now) - acp.openingDate) / 7  AS duration_aggregator');
+
                 break;
 
+            case 'month':
+                $qb->addSelect('(EXTRACT (MONTH FROM AGE(COALESCE(acp.closingDate, :now), acp.openingDate)) * 12 +
+                    EXTRACT (MONTH FROM AGE(COALESCE(acp.closingDate, :now), acp.openingDate))) AS duration_aggregator');
 
+                break;
+
+            default:
+                throw new LogicException('precision not supported: ' . $data['precision']);
         }
 
-        // TODO Pour avoir un interval plus précis (nécessaire ?):
-        // adapter la fonction extract pour pouvoir l'utiliser avec des intervals: extract(month from interval)
-        // et ajouter une fonction custom qui calcule plus précisément les intervals, comme doctrineum/date-interval
-        // https://packagist.org/packages/doctrineum/date-interval#3.1.0 (mais composer fait un conflit de dépendance)
-
-        $qb->addGroupBy('duration_aggregator');
-        $qb->addOrderBy('duration_aggregator');
+        $qb
+            ->setParameter('now', new DateTimeImmutable('now'))
+            ->addGroupBy('duration_aggregator')
+            ->addOrderBy('duration_aggregator');
     }
 
     public function applyOn(): string
@@ -71,7 +79,7 @@ final class DurationAggregator implements AggregatorInterface
         $builder->add('precision', ChoiceType::class, [
             'choices' => array_combine(self::CHOICES, self::CHOICES),
             'label' => 'export.aggregator.course.duration.Precision',
-            'choice_label' => fn (string $c) => 'export.aggregator.course.duration.'.$c,
+            'choice_label' => static fn (string $c) => 'export.aggregator.course.duration.' . $c,
             'multiple' => false,
             'expanded' => true,
         ]);
@@ -79,20 +87,16 @@ final class DurationAggregator implements AggregatorInterface
 
     public function getLabels($key, array $values, $data)
     {
-        return function ($value): ?string {
+        return static function ($value) use ($data) {
             if ('_header' === $value) {
-                return 'Rounded month duration';
+                return 'export.aggregator.course.duration.' . $data['precision'];
             }
 
             if (null === $value) {
-                return $this->translator->trans('current duration'); // when closingDate is null
+                return 0;
             }
 
-            if (0 === $value) {
-                return $this->translator->trans('duration 0 month');
-            }
-
-            return $value . $this->translator->trans(' months');
+            return $value;
         };
     }
 
diff --git a/src/Bundle/ChillPersonBundle/translations/messages.fr.yml b/src/Bundle/ChillPersonBundle/translations/messages.fr.yml
index 55014637a..7e9fbfeaa 100644
--- a/src/Bundle/ChillPersonBundle/translations/messages.fr.yml
+++ b/src/Bundle/ChillPersonBundle/translations/messages.fr.yml
@@ -951,3 +951,8 @@ export:
                 Group course by referrer's scope: Grouper les parcours par service du référent
                 Computation date for referrer: Date à laquelle le référent était actif
                 Referrer's scope: Service du référent de parcours
+            duration:
+                day: Durée du parcours en jours
+                week: Durée du parcours en semaines
+                month: Durée du parcours en mois
+                Precision: Unité de la durée