public function calculate(Collection $applicants, EsiQuestions $question): EsiSingleDataObject 	{ 		$esiDataObject = new EsiSingleDataObject;  		$applicantsCount = $applicants->count();  		if ($applicants->isNotEmpty()) { 			$average = $applicants->avg($question->value) ?? 0;  			$esiDataObject->setAverage($average);  			$applicants->groupBy($question->value)->each(function (Collection $items, $key) use ($applicantsCount, $esiDataObject) { 				$esiDataObject->{(is_numeric($key) && ($key >= 1) && ($key <= 10)) ? $key : 11} = round(($items->count() / $applicantsCount) * 100); // 11 means not answer 			}); 		}  		return $esiDataObject; 	}