public function getSaldo(BankAccount $bankAccount)
 {
     $repo = $this->entityManager->getRepository('HomefinanceBundle:Transaction');
     $transactions = $repo->findBy(array('administration' => $bankAccount->getAdministration(), 'bank_account' => $bankAccount));
     $total = (double) $bankAccount->getStartingBalance();
     foreach ($transactions as $t) {
         $total = $total + $t->getAmount();
     }
     return $total;
 }