    function calculateBonus(uint256 timeElasped , uint256 amount) public view  returns(uint256){
        uint256 totalDays = timeElasped.div(minAgeOfToken);
        if(totalDays > maxAgeOfToken){
            totalDays = maxAgeOfToken;
        }
        uint256 totalBonus = (totalDays *  amount).div(perDayBonus);
        return totalBonus;
    }