    function getInvestor(address _investor, uint _index) public view returns(string, uint, uint, bool, uint, uint) {
        return (
            investments[_investor][_index].currency,
            investments[_investor][_index].rate,
            investments[_investor][_index].amount,
            investments[_investor][_index].redeemed,
            investments[_investor][_index].timestamp,
            investments[_investor][_index].tokens
        );
    }