From time to time I'll compile trend information on USC's performance using available statistics for the Pete Carroll era. In addition to the long term look I'll compile the individual game by game trends within a season and when of interest drill down into specific plays within a given season. Here is the annual look at the USC performance on defense for several major categories in Pac-10 play.
For starters here is the USC rush defense looked at in terms of yards allowed per game over the past seven year. As a whole it ranks #1 in the Pac-10 and has been fairly consistent in the five of the seven years. The two exceptions are 2001 the first year under a new staff and 2005 when USC's defense struggled at key points during the season. The only Pac-10 team to keep reasonably close to USC during this time period has been Oregon State who lead the nation in rush defense in 2007. The other interesting team in the data set is UCLA who would rank higher in run defense if it were not for the disastrous years of 2004 and 2005 where they ranked last in the Pac-10. The two years following that under former USC and NFL coach DeWayne Walker they have much improved in this dimension.
USC also leads the conference over the past seven years in terms of Pass Yardage Defense overall. The strongest two years in terms of limiting yardage were 2001 (weak rush defense season) and 2007 where USC allowed 189.0 yards overall. The next closest team in the conference is Oregon State followed by UCLA.
In terms of total defense it is no surprise that USC again comes out on top with an average 308.4 yards allowed per game. The worst year in terms of yardage allowed was 2005 at 360.9 yards which ranked a mere 48th in the nation in this category. The 2007 allowed the fewest yards overall for the Pete Carroll era just edging out the 2004 team. Oregon State is a fairly close second in the conference. UCLA comes in third mainly due to the off seasons of 2004 and 2005.
Here is a look at the passing defense in terms of percentage of completions allowed. Here Oregon State ranks a clear first (but their YPC is last in the conference - see below), then there are several tightly clustered teams around 53 to 54% completions allowed. USC ranks 4th in the conference over the period in question.
However just looking at pass completions alone can be misleading as you see in the next set of data. USC ranks on top in terms of average gain allowed per completion despite giving up a higher percentage. USC has been fairly constant in this regard averaging between a low of 10.2 yards per completion in 2007 and a high of 11.6 YPC in 2002. The next closest team in the conference is UCLA. Oregon State which gave up the lowest percentage of completions allowed ranks last in the conference in terms of YPC at 13.2. Some of that is driven by one really bad season in 2005 it appears but still on average they rank towards the bottom in terms of preventing big plays in the passing game.
Yards per attempt is another check on the passing data and here you can see USC maintains its #1 position with a fairly consistent performance overall. The YPA figure varies between 5.5 yards allowed in 2007 and 6.3 yards allowed in 2003. Oregon State on the strength of its pass completion percentage defense moves up in this category to rank second at 6.6 followed closely by UCLA, Washington State, and Oregon.
Turnovers is another key category to look at and I'll the pass interceptions trend. Here USC leads by a small margin of Oregon State and Oregon. USC had been very strong in this area under Pete Carroll from 2001 to 2005 averaging over 20 per season. That trend fell off a cliff the past two years however and declined nearly in half to 11 interceptions in 2006 and 12 in 2007. Fixing this category is a big area for improvement in 2008.
The final stat I'll compare is the scoring defense for the Pac-10 over the past seven years. No surprise that USC again comes out on top in this dimension. For six of the seven years in the Pete Carroll era the defense has been pretty consistent allowing a low of 13.0 points per game in 2004 and an average of 17.4 points per game overall. The only real aberration in the data was 2005 when the defense allowed 22.8 points per game and struggled at times after the lost of talent from the 2004 squad and of course injuries. The past two seasons it has rebounded nicely. Oregon State is second in the conference over the past seven years followed closely by UCLA and Cal.
There are a few other areas I'd like to include such as 3rd down defense, sacks, tackles for loss, etc. However the NCAA data only offers those from about two years ago and forward. That is too small a period to look at for any trends. For just USC year by year trend data you can find those areas listed here.