diff --git a/src/services/queryRunner.service.ts b/src/services/queryRunner.service.ts
index f4dd66206df7a83796b1b21740d03fe954152f9b..bc840585457903e2acbc00b45937176b823ab23f 100644
--- a/src/services/queryRunner.service.ts
+++ b/src/services/queryRunner.service.ts
@@ -111,18 +111,16 @@ export default class QueryRunner {
     timePeriod: TimePeriod,
     timeStep: TimeStep
   ) {
-    const filterData = (
-      entry: any,
-      timeStep: TimeStep,
-      timePeriod: TimePeriod
-    ) => {
+    if (timeStep === TimeStep.HALF_AN_HOUR) {
+      // increase timeperiod range because the last data for a day is actually stored the next day at 00:00
+      timePeriod.startDate = timePeriod.startDate.plus({ minutes: 30 })
+      timePeriod.endDate = timePeriod.endDate.plus({ minutes: 30 })
+    }
+
+    const filteredResult = data.data.filter((entry: any) => {
+      // add ternary expression to not send to the withinDate function an hour different than zero
       const hour = timeStep === TimeStep.HALF_AN_HOUR ? entry.hour : 0
       const min = timeStep === TimeStep.HALF_AN_HOUR ? entry.minute : 0
-      if (timeStep === TimeStep.HALF_AN_HOUR) {
-        // increase timeperiod range because the last data for a day is actually stored the next day at 00:00
-        timePeriod.startDate = timePeriod.startDate.plus({ minutes: 30 })
-        timePeriod.endDate = timePeriod.endDate.plus({ minutes: 30 })
-      }
       return this.withinDateBoundaries(
         DateTime.local(
           entry.year,
@@ -135,10 +133,7 @@ export default class QueryRunner {
         }),
         timePeriod
       )
-    }
-    const filteredResult = data.data.filter((entry: any) =>
-      filterData(entry, timeStep, timePeriod)
-    )
+    })
     return filteredResult
   }