Nokia Lumia :: Semi-scientific Test On Battery Life Post Portico?

I have a red 920.So I charged my battery to 100% and took it off the charger. This was in the middle of the night (yes, I'm a night owl). But I did it because I wanted to test it with absolutely no use. So I set the wifi to always on and left the phone. four hours later I checked the battery. It was down to 60%. This was after absolutely no use. The only thing I have is two email accounts set to fetch every hour.

i then recharged to 100% again, changed the wifi settings back to the original setting and left it for another 4 hours. The battery was down to 63%. Not that much different from setting wifi to always on.However, previously my phone would lose at most 1% after idle for even 8 hours. As I stated my battery life has always been very good.the only difference was the OS update, no new apps, no setting changes, etc. I have to assume it was the update. I know it's not really scientific and partially anecdotal but it is what it is.