function getMonthsPassedEndOfSinceIco() onlyWhenIcoParametersAreSet internal view returns (uint8) {
    uint256 timePassedSinceIco = now - icoEndDate;
    uint8 monthsPassedSinceIco = uint8(timePassedSinceIco / weekLength);
    return monthsPassedSinceIco + 1;
  }