Hotels in Athens have seen bookings drop sharply over the last few days after an ash cloud from an Icelandic volcano grounded hundreds of flights scheduled to have arrived in Greece, said Yiannis Retsos, president of the Athens-Attica Hotel Association. The latest blow to the tourism sector in Athens may result in a greater-than-expected drop in sector revenues this year, added Retsos. According to the most recent estimates, income in the tourism sector is likely to fall by an annual rate of between 6 and 8 percent. On Monday, Aegean Airlines said that the canceled flights are costing the company up to 600,000 euros per day. Press reports said yesterday that Aegean rival Olympic Air is also losing about 400,000 euros a day due to the disruption in air travel across Europe.