Daily deal sites like Groupon and LivingSocial saw rapid growth between 2008-2011, with revenues projected to reach $3.9 billion by 2015. These sites partner with local businesses to offer daily deals and coupons to subscribers within a certain zip code. While some merchants had success, others found that the business gained did not offset the commission taken by the daily deal site. Experts believe the market is becoming oversaturated and daily deal sites will need to focus on retaining existing customers rather than coupon-seekers to survive long-term.