Around what is advertised. Remember that there are many other factors that come into play as well, so if you're getting slightly less than the advertised 8 on data/10 on Wifi, meaning something like 6.5/9 or so, then your battery is fine. It'd also be better to limit some of the other innate features as well, such as Location System Services, data fetching and pushing, etc as they do put a damper on your battery if you're battery conscious.