角度求和过滤器的值

Question

我正在添加一些值。但是，当我对其进行过滤时，值不会改变。当任何人选择仅显示那个policy_id的总和的策略时，我需要更改总和。

 getClaims(){

  if(this.userFilter.company_id){


  this.url = 'http://api.igiinsurance.com.pk:8888/insurance_IGItakaful/insurance-api/get_claims.php?offset=0&limit=1000&company_id='+this.userFilter.company_id;

  this.spinner.show();

 }
  else{

  this.url = 'http://api.igiinsurance.com.pk:8888/insurance_IGItakaful/insurance-api/get_claims.php?offset=0&limit=50';
            this.spinner.show();

  }
 this.clientData = this.httpClient.get<any>(this.url).
 subscribe(data => {
 console.log(data);
         this.spinner.hide();

         this.data = data.records;
         this.data.forEach(d => this.policy_id.add(d.policy_id));



 var status = 'settled';
 var status2 = 'submitted';

 var countsettled = this.data.filter((obj) => obj.status === status).length;
 var countunsettled = this.data.filter((obj) => obj.status === status2).length;

 console.log(countsettled);
 this.countsettled = countsettled;
 console.log(countunsettled);
 this.countunsettled = countunsettled;

 const sum1 = this.data.filter(item => item.status === 'settled')
                 .reduce((acc, item) => acc + Number(item.approved_value), 0);
                 console.log(sum1);
                 this.sum1 = sum1;

 const sum2 = this.data.filter(item => item.status === 'submitted')
                 .reduce((acc, item) => acc + Number(item.approved_value), 0);
                 console.log(sum2);
                 this.sum2 = sum2;


     });
  }
}

.html

<div class="col-md-3">
  <div class="form-group">
     <label for="">Policy</label>
        <select class="form-control" [(ngModel)]="userFilter.policy_id" >
           <option *ngFor="let policy of policy_id" value="{{policy}}">{{policy}}</option>

        </select>
   </div>
</div>

如果用户选择“策略”，我需要对值求和。有人可以帮忙吗，谢谢