I participate in the Google Adsense Program and I recently got a Coupon in the mail for $100 worth of Adwords money. Well the first date expired and now the total has dropped from $100 to $50. I really want to use the $50 but my site is not ready. The offer expires at the end of the month. My question is can I load the money into an account then hold onto it for a month or two or even a year for instance, while I finish my site? or do I have to load the money and use it all by the expiration date?