What happens when your sites are down for a week?

I just moved all of my sites to a new host. As a result, they were all down for a week and traffic is at a complete standstill due to all of their SERPs being demolished.

Anyone have any experience with this or know what the consequences are with your rankings when a site is down for a week? I've had them back up for about 10 days now and it's still pretty bad.

Thanks...

I loss my SERP and traffic but after some time everything is fine..