function getInterest(uint value, uint lastCalculated) public view returns (uint) {
    if(value == 0) {
      
      
      return 0;
    }
    uint exp = (block.timestamp - lastCalculated) / 3600;
    uint x = 1000000000000000000;
    uint base = 1000000000000000000 + hourRate;
    while(exp != 0) {
      if(exp & 1 != 0){
        x = (x * base) / 1000000000000000000;
      }
      exp = exp / 2;
      base = (base * base) / 1000000000000000000;
    }
    return value.mul(x - 1000000000000000000) / 1000000000000000000;
  }