How many PPG will the offense Score?

[over the mountain]

seems that scoring has gone up every year since 2005 (as expected)

2005 - 20.6 ppg (for entire NFL)
2013 23.4 ppg (NFL)

NFL Season By Season Team Offense - Pro-Football-Reference.com

Redskins

2013 20.9
'12 27.3
'11 18
10 18.9
09 16.6 (zorn)
08 16.6 (zorn)
'07 20.9 (gibbs)
06 19.2
05 22.4

3 things stand out to me

2012 was a very special year for us and i loved it.
Zorn was worse than I thought
Gibbs II was better than I thought

edit - i was inclined to discount the record setting avg PPG of 23.4 last year bc the broncos avg something insane like 37 ppg but going forward i could see one or two teams a year putting up insane scoring numbers. its the norm now to expect offensive records to be broken every year.