Guild level:69, Member Count: 32
Renown lost = (LevelMultiplier * AccountMultiplier)
Renown lost = (517.40 * (32 + 10))
Daily Decay = 21,731 renown (~315 heroic deeds/day)
The higher we go, the more we have to fight for it, so don't forget to grab that renown if you don't need the other end rewards. I would be more than happy to help out some of the newer guild members with platinum to make it easier at the low levels.
That said, congratulations on level 69, we've all earned it!