Groupon (NYSE:GRPN) showing signs the online deal market is dwindling. The company posted a 45% rise in second quarter revenue to $568.3 million, a positive number for the online deal site but a negative one for Wall Street. Analysts were expecting revenue to be $575.3 million. Groupon said they missed estimates because of weakness in Europe which resulted in poor sales internationally. The company added it hopes to boost its business in that region for the coming quarter.Looking ahead, the company sees revenue between $580 million to $620 million, more or less in line with the average analyst estimate of $607.4 million.