Here are some defensive stats from last year:
FOOTBALL OUTSIDERS: Innovative Statistics, Intelligent Analysis | 2014 DEFENSIVE EFFICIENCY RATINGS
Football Outsiders Defensive Efficiency Stats:
Overall Defense: 30th
Pass Defense: 32nd Dead Dog Last
Rush Defense: 9th
I like the above FBO defensive stats because raw yards and even points doesn't completely isolate the defense from special teams and offense.
Other stats I like to judge the defense:
NFL Stats: by Team Category
QB rating against: 108.3 or Dead Dog Last
YPA against: 8.2 tied w/ ATL for Dead Dog Last
Total Interceptions: 7 tied for 4th least
Sacks: 36 tied for 21st