Correção para quando os dados ainda não foram populados e o HTML já foi carregado

src/app/simulator/access-and-offer/view-enrollment-by-stage-series/view-enrollment-by-stage-series.component.html

@@ -3,7 +3,7 @@
     <div class="page-header">
       <h1 class="page-title">{{functionality.name}}</h1>
       <h3 class="page-subtitle">
-        {{functionality.subtitle.replace('{outOfSchoolPopulationCurrentYear}', data.outOfSchoolPopulationCurrentYear.toString()).replace('{enrollmentCurrentYear}', data.enrollmentCurrentYear.toString())}}
+        {{functionality.subtitle.replace('{outOfSchoolPopulationCurrentYear}', data.outOfSchoolPopulationCurrentYear?.toString()).replace('{enrollmentCurrentYear}', data.enrollmentCurrentYear?.toString())}}
       </h3>
     </div>
     <div class="panel panel-default">