Download ES task manager, close all programs, kill all tasks, hell, do a reboot just for the hell of it and check if your findings are the same. This might be a faulty battery, but just might be some background process that's remaining active. If all else fails a factory reset is worth a shot to make sure.
Last night I took my device off of a full charge at 7PM, used it almost constantly for all kinds of tasks, web browsing, Chromecast streaming off of Hulu, a bit of YouTube and various other apps. I took a break around 9PM for about 90 minutes, but other than that I used it consistently until 1PM and at that point there was 26% charge left. Not bad for the amount of use I gave it.