A look at $1.9B Powerball jackpot and how it grew so large.

DES MOINES, Iowa Monday night's estimated $1.9 billion Powerball jackpot is nearly $400 million larger than the previous record jackpot and will keep growing until someone finally wins the prize. The jackpot started at $20 million back on Aug. 6 and over three winless months has grown to be 95 times as large. Those who spend $2 on a Powerball ticket might wonder if…