function updateStatementCountByBuildingPermit(string memory buildingPermitId) internal {
    uint oldCount = statementCountByBuildingPermitHash[keccak256(abi.encodePacked(buildingPermitId))];

    if(oldCount == 0) { 
      buildingPermitIds.push(buildingPermitId);
    }

    uint newCount = oldCount + 1;
    assert(newCount > oldCount);
    statementCountByBuildingPermitHash[keccak256(abi.encodePacked(buildingPermitId))] = newCount;
  }