diff --git a/backend/src/graphql/model/Decay.ts b/backend/src/graphql/model/Decay.ts
index 591294df5..46aef4263 100644
--- a/backend/src/graphql/model/Decay.ts
+++ b/backend/src/graphql/model/Decay.ts
@@ -1,18 +1,16 @@
 import { ObjectType, Field, Int } from 'type-graphql'
 import Decimal from 'decimal.js-light'
 
-interface DecayInterface {
-  balance: Decimal
-  decay: Decimal
-  roundedDecay: Decimal
-  start: Date | null
-  end: Date | null
-  duration: number | null
-}
-
 @ObjectType()
 export class Decay {
-  constructor(data: DecayInterface) {
+  constructor(data: {
+    balance: Decimal
+    decay: Decimal
+    roundedDecay: Decimal
+    start: Date | null
+    end: Date | null
+    duration: number | null
+  }) {
     this.balance = data.balance
     this.decay = data.decay
     this.roundedDecay = data.roundedDecay