diff --git a/package.json b/package.json
index c797c44b9..543407889 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
 	"name": "mon-entreprise",
 	"license": "MIT",
-	"version": "1.2.3",
+	"version": "1.2.6",
 	"description": "Library to compute the french social security contributions. Also a website that explains the calculations, and a generic engine to build cool forms that asks the question needed to compute an objective.",
 	"main": "./dist/engine.js",
 	"files": [
diff --git a/source/engine/index.js b/source/engine/index.js
index a3168d45b..fe09942bb 100644
--- a/source/engine/index.js
+++ b/source/engine/index.js
@@ -28,12 +28,16 @@ class Engine {
 		this.parsedRules = parseAll(rules)
 		this.defaultValues = collectDefaults(rules)
 	}
-	evaluate(targets, { defaultUnits, situation }) {
+	evaluate(targets, { defaultUnits, situation, withDefaultValues = true }) {
 		this.evaluation = analyseMany(
 			this.parsedRules,
 			targets,
 			defaultUnits
-		)(dottedName => situation[dottedName] || this.defaultValues[dottedName])
+		)(
+			dottedName =>
+				situation[dottedName] ||
+				(withDefaultValues && this.defaultValues[dottedName])
+		)
 		return this.evaluation.targets.map(({ nodeValue }) => nodeValue)
 	}
 	getLastEvaluationExplanations() {