2005 Eagles were 23rd overall in total defense which is yards (325.4) per game. They were 26th in scoring defense which is points (24.2) allowed per game. I go by conference. The lowest (16th) is rated 60 with the highest (1st) rated 98. 98 is the maximum and 60 is the minimum. My rating setup is the same as the drafted rookies as well as player attributes and overall rating. Eagles are 68 in total defense and 70 in scoring defense. Because the ratings cant meet, I go with the higher rating which is 70. Add in the missed games by the starters and it becomes 72 which is still crappy for them. You'll easily see the difference between the 2004 Eagles defense which is 95 overall the 2005 Eagles defense which will be 72 overall.
Dont be shocked if no one is in the 90's. Of course, having lower rated backups decreases the overall rating but you'll see few if any of them in the 90's. I havent even tested anything out and wont until later on since im concentrating on getting my 2004 (2K5) roster done in January.
For team ratings, I go by total offense/defense and scoring offense/defense. Here's an example of the 2004 Cowboys defense which was ranked 7th in total defense but 14th in scoring defense. Remember that this is based on conference, not league.
Total Defense: 82 - 80 / 77 / 75
Scoring Defense: 65 - 68 / 70 / 72
The higher rating gets decreased while the lower rating gets increased to where they're both the same. If they dont meet, I go with the higher rating which in this case would be 75. The starters only missed 8 games total and because my minimum is 11, there's no rating increase whatsoever. The Cowboys defense will be rated 75 overall for the 2004 season in my roster.
Here's an offensive example of the Buffalo Bills -
Total Offense: 68 - 70 / 72 / 75 / 77
Scoring Offense: 88 - 85 / 82 / 80 / 77
Both ratings meet which would give them a 77 overall rating for offense but the starters missed a total of 11 games which equals one slot increase, thus giving them an 80 overall rating. Bills are rated 95 defensively including two slot increases.
Hope this explains how I setup everything. I'll have better explainations when I post my roster and franchise files.