```\\nfunction _takeDonationFee(uint256 tDonation) private {\\n    uint256 currentRate = _getRate();\\n    uint256 rDonation = tDonation.mul(currentRate);\\n    _rOwned[_donationAddress] = _rOwned[_donationAddress].add(rDonation);\\n    if (_isExcluded[_donationAddress])\\n        _tOwned[_donationAddress] = _tOwned[_donationAddress].add(\\n            tDonation\\n        );\\n}\\n```\\n