diff --git a/packages/api-derive/src/elections/voters.ts b/packages/api-derive/src/elections/voters.ts
index 420a190290..bb5026ccf1 100644
--- a/packages/api-derive/src/elections/voters.ts
+++ b/packages/api-derive/src/elections/voters.ts
@@ -29,7 +29,7 @@ export function voters (api: ApiInterfaceRx): () => Observable<Vector<AccountId>
           new Vector(
             AccountId,
             Object.keys(voterSets).map(
-              address => new AccountId(address)
+              (address: string): AccountId => new AccountId(address)
             )
           )
       ),
diff --git a/packages/api-derive/src/types.ts b/packages/api-derive/src/types.ts
index fa8ae466db..3f202fca31 100644
--- a/packages/api-derive/src/types.ts
+++ b/packages/api-derive/src/types.ts
@@ -32,7 +32,7 @@ export interface DerivedContractFees {
 }
 
 export interface DerivedElectionsInfo {
-  members: [AccountId, BlockNumber][];
+  members: Record<string, BlockNumber>;
   candidates: AccountId[];
   candidateCount: BN;
   desiredSeats: BN;