NFL: A close look at the defenses of 2015

Total Defense (YPG)
1) NY Jets (269.2)
2) Denver Broncos (281.3)
3) Seattle Seahawks (294.1)
4) Tennessee Titans (313.6)
5) Tampa Bay Buccs (322.8)

Passing (YPG)
1) Tennessee Titans (184.0)
2) NY Jets (186.6)
3) Denver Broncos (192.2)
4) Seattle Seahawks (200.0)
5) Tampa Bay Buccs (202.4)

Rushing (YPG)
1) Atlanta Falcons (78.8)
2) NY Jets (82.6)
3) Oakland Raiders (83.2)
4) Buffalo Bills (87.2)
5) Denver Broncos (89.2)

Sacks
1) Denver Broncos (26.0)
2) Green Bay Packers (23.0)
3) New England Patriots (19.0)
4) Seattle Seahawks (19.0)
5) St. Louis Rams (19.0)

Points Per Game Allowed
1) NY Jets (15)
2) Minnesota Vikings (16.6)
3) Green Bay Packers (16.8)
4) Denver Broncos (17.0)
5) Pittsburgh Steelers (18.0)

(This stat is kind of misleading considering Denver's defense has only allowed 13.5 PPG. Denver has had 3 INTs returned for touchdowns this season. Not sure about all of the other teams.)

Forced Turnovers
1) Denver Broncos (17)
2) Philly Eagles (16)
3) NY Jets (15)
4) Arizona Cardinals (13)
5) Carolina Panthers and NY Giants (11)

3rd Down % Given Up
1) Houston Texans (31.3%)
2) Denver Broncos (31.6%)
3) Seattle Seahawks (31.8%)
4) NY Jets (32.4%)
5) San Diego Chargers (33.8%)

Given the numbers, how would you rate the NFL defenses in 2015 so far?

I'm surprised to see Tennessee and Atlanta doing so well after last season.