diff --git a/src/app/asset-calculator/asset-calculator.component.ts b/src/app/asset-calculator/asset-calculator.component.ts
index e7c4825..e25cab9 100644
--- a/src/app/asset-calculator/asset-calculator.component.ts
+++ b/src/app/asset-calculator/asset-calculator.component.ts
@@ -74,9 +74,12 @@ interface FormValues {
 
 				this.addChangeValue();
 	
-				const row = this.lifeFormArray.controls[ i -1 ] as FormGroup;
-				row.get( 'initialValueAsset' )?.setValue(asset.life[i].initial);
-				// row.get( 'year_month' )?.setValue( asset.life[i].when.toFormValue());
+				const row : FormGroup = this.lifeFormArray.controls[ i - 1 ];
+				const lifeChange : AssetLifeChange = asset.life[i];
+				row.get( 'initialValueAsset' )?.setValue( lifeChange.initial);
+				const ym : YearMonth = lifeChange.when;
+				//const when_txt = ym.toFormValue();
+				row.get( 'year_month' )?.setValue( lifeChange.when.year +'-' +  lifeChange.when.month );
 	
 			
 			}
diff --git a/src/app/asset-calculator/assets/asset.ts b/src/app/asset-calculator/assets/asset.ts
index c827b6f..4167b94 100644
--- a/src/app/asset-calculator/assets/asset.ts
+++ b/src/app/asset-calculator/assets/asset.ts
@@ -6,14 +6,21 @@ export enum TypeDepreciation{
 export class YearMonth{
     readonly year  : number ;
     readonly month : number ;
-    constructor( year_month:string ){
-        const [ year, month ] = year_month.split( '-').map(Number);
-        this.year = year;
-        this.month =month;
+
+    constructor( year_month:string | YearMonth ){
+        if (typeof year_month === 'string') {
+            const [year, month] = year_month.split('-').map(Number);
+            this.year = year;
+            this.month = month;
+        } else {
+            this.year = year_month.year;
+            this.month = year_month.month;
+        }
         
     }
-    toFormValue(){
-        return this.year + "-" + this.month;
+    
+    toFormValue() {
+        return `${this.year}-${this.month.toString().padStart(2, '0')}`;
     }
 }