angular typescript declare generic with empty object

I am trying to declare following variable in angular 12

private subject = new BehaviorSubject<ApiResponse>({});

I get error

Argument of type '{}' is not assignable to parameter of type 'ApiResponse'
Type '{}' is missing the following properties from type 'ApiResponse'

The class ApiResponse has following properties

export interface ApiResponse {
  success: boolean
  message: string
  exception: any
  totalRowCount: number
}

If I declare each property explicitly, it works without error
Is there a way to declare an empty object without declaring each property explicitly ?

>Solution :

Use ? for optional properties

export interface ApiResponse {
  success?: boolean;
  message?: string;
  exception?: any;
  totalRowCount?: number;
}