<prompt> Translate the following text to EnglishKwa madhumuni ya simulation hii, kiasi cha vyanzo vya kuhifadhiwa kutoka 2002 hadi 2006 kilihesabiwa kama tofauti ya kawaida kati ya makadirio ya kesi ya kumbukumbu na trajectory ya uzalishaji halisi ya kila hali.  <response>: For purposes of this simulation, the amount of allowances banked from 2002 through 2006 was calculated as the simple difference between the reference case projections and the actual emission trajectory of each scenario. 