First time I heard this figures of bounce rate. This is totally great but the webmasters most rely on google analyics report.
Buddy, Bounce rate of 5% means that out of the visitors that come to your site only 5% go away after looking at the site. 5% is too good man, even if in coming years you go up till 15%, you'll be among the sites will minimum bounce rates across the world.
wow. dude its really cool. my site's bounce rate reached to 70% once. but now i have controlled it and its 32% now... nyways best of luck..