Defensive Shutouts NFL 2008?

[SPEEDY]

How many total Defensive Shutouts were there last season?

[Tiptoe_Stevens]

Carolina shut out Kansas City 34-0 in Week 5. link
Atlanta shut out Oakland 24-0 in Week 9. link
Cincinnati shut out Cleveland 14-0 in Week 16. link
Indianapolis shut out Tennessee 23-0 in Week 17. link
New England shut out Buffalo 13-0 in Week 17. link
Pittsburgh shut out Cleveland 31-0 in Week 17. link