function getExchangeRate() constant returns(uint){
        
        if(fundingStart + 1 * 1 days > block.timestamp){
            return 15000;
        }
        
        else{
            uint256 decrease=100-(soldAfterPowerHour/10000000/1000000000000000000);
            if(decrease<70){
                decrease=70;
            }
            return 10000*decrease/100;
        }
    }