function updateFeeForCurrentStakingInterval() external onlyOperator isDoneStaking {
    require(feeCalculated == false);
    uint feeReceived = feeToken.balanceOf(this);
    feeForTheStakingInterval = feeForTheStakingInterval.add(feeReceived.add(this.balance.div(weiPerFee)));
    feeCalculated = true;
    FeeCalculated(feeForTheStakingInterval, feeReceived, this.balance, startBlock, endBlock);
    if (feeReceived > 0) feeToken.burnTokens(feeReceived);
    if (this.balance > 0) wallet.transfer(this.balance);
  }