Andrew Zhu

A Perfect Week for Cheese



Just so you know, every day is a perfect day for cheese – but I should watch how much I consume

I was reading up the other day on all-time great college football rivalries: Michigan – Ohio State, Alabama – Auburn, or Oklahoma – Texas, to name a few. Scrolling through the Wikipedia entry of the USC Trojans football team, I came across an intriguing term of a “Perfect Day,” coined by their longtime football announcer, Pete Arbogast. His definition of a Perfect Day is a USC football victory combined with losses by rivals Notre Dame and UCLA. Apparently there have been at least 63 Perfect Days in the history of USC football, which seems low to me, but then again Notre Dame, at least, has been quite excellent for the majority of their seasons.

That got me thinking – how many “Perfect Days” have there been in the history of the Green Bay Packers franchise? Of course, as not all NFL games are played on Sundays, I decided to redefine “Perfect Day” as “Perfect Week,” meaning a victory by the Packers in the same week as defeats by the Chicago Bears, Detroit Lions, and Minnesota Vikings.

A Perfect Week for Cheese

Scraping the whole of Pro Football Reference for all games played by the 32 NFL teams from the start of the 1920 season to the end of the 2020 season resulted in a spreadsheet with more than 33,300 rows. A decent number of these rows consisted of playoff games or bye weeks, though I estimate that probably 10-15k regular season NFL games have been played by the still-existing teams. I was able to greatly cut down the number of games by removing all games before the 1960 season, which marked the season when expansion teams formed. Therefore, even in the oldest NFL divisions (NFC North, NFC East), their newest member only began play in 1960.

It should be noted that the current method of dividing the league into eight divisions of four teams was only finalized in 2002 with the addition of the Houston Texans. Furthermore, divisions have also changed in composition throughout NFL history, illustrated by the example of the Tampa Bay Buccaneers, who were longtime members of the NFC Central (along with the four current NFC North teams). For the purposes of this analysis, I will consider the current NFL division structure: in other words, the Buccaneers will be considered a part of the NFC South (1996 – present) even though they were previously classified as a NFC Central team, and AFC West team before that.

I got carried away with the analysis, so I ran it for all eight divisions in the NFL, through the end of the 2020 NFL regular season.

NFC North (1961 - 2020)

Number of Seasons: 60

Perfect Weeks: 50 (Green Bay Packers), 47 (Minnesota Vikings), 44 (Chicago Bears), 26 (Detroit Lions)

Most Perfect Weeks in a season: 4 (1979 Chicago Bears, 2002 Green Bay Packers)

In the 1960s, we see the Packers jump out in front on the strength of five NFL titles, after which the Purple People Eaters take the lead in 1970s. It’s a close race as the strong Bears teams of the 1980s rack up numbers in the Perfect Week column. The Vikings, Bears, and Packers battle it out through the 2000s and 2010s, with the Packers finally regaining a small breathing space over the last several years. As it stands today it’s a close three-team race at the top with the Lions lagging far behind.

NFC East (1960 - 2020)

Number of Seasons: 61

Perfect Weeks: 52 (Dallas Cowboys), 46 (Washington Football Team), 43 (Philadelphia Eagles), 39 (New York Giants)

Most Perfect Weeks in a season: 4 (2020 Dallas Cowboys, 1962/1963 New York Giants, 1964 Philadelphia Eagles, 2015 Washington Redskins)

The NFC East has always been a hotbed of competition as all four teams have had their days of glory. I am a little surprised that the New York Giants are last in the running, though the margin is quite slim. As the Cowboys hold one of the top win-loss records since their franchise start in 1960, unsurprisingly, they lead the field.

NFC South (1995 - 2020)

Number of Seasons: 26

Perfect Weeks: 29 (New Orleans Saints), 22 (Carolina Panthers), 21 (Tampa Bay Buccaneers), 17 (Atlanta Falcons)

Most Perfect Weeks in a season: 5 (1996 Carolina Panthers)

As the most recent NFC division – given the relative infancy of the Carolina Panthers franchise – there haven’t been too many total Perfect Weeks in this division. The Sean Payton-led Saints have generally been the best team in the division over the past decade, and the Saints current lead by a decent margin.

NFC West (1976 - 2020)

Number of Seasons: 45

Perfect Weeks: 48 (San Francisco 49ers), 43 (Los Angeles Rams), 35 (Seattle Seahawks), 27 (Arizona Cardinals)

Most Perfect Weeks in a season: 5 (1980 Los Angeles Rams, 2000 St. Louis Rams)

The astute NFL observer will note that Seattle Seahawks were actually an AFC team to begin with, but let’s not dwell on semantics here! This division is really a two-team race, as the 1970s Los Angeles Rams shot out ahead until the Bill Walsh dynasty brought the 49ers on top in the 1990s. While the Greatest Show on Turf made the race close, the 49ers still hold a lead of five after the 2020 NFL season.

Now that we are halfway through the divisions, with the NFC complete and the AFC to go, let’s summarize the results thus far. As expected, there are more Perfect Weeks in the older divisions (NFC North, NFC East) compared with the younger divisions (NFC South, NFC West), as there were simply more weeks/seasons that were played. To adjust for this, we can normalize the numbers by dividing total number of perfect weeks by the number of weeks played for each team, including byes:

It is also interesting to consider the hypothetical maximal number of Perfect Weeks in a 16 game season. Assuming that all division teams’ bye week falls on the same week, and that all division head-to-head games are played over the same six weeks, then a team can potentially record 10 Perfect Weeks. Thus far, the most we have seen is five, but will an AFC team have more?

AFC North (1999 - 2020)

Number of Seasons: 22

Perfect Weeks: 24 (Baltimore Ravens), 18 (Pittsburgh Steelers), 12 (Cincinnati Bengals, Cleveland Browns)

Most Perfect Weeks in a season: 4 (2000/2019 Baltimore Ravens)

The Perfect Week leader has been held solely or in part by the Ravens since formation of the division, and they have managed to increase the gap to the second-place Steelers over the past few seasons. There already is a significant gap of several Perfect Weeks from the Steelers to the Bengals and Browns.

AFC East (1966 - 2020)

Number of Seasons: 55

Perfect Weeks: 58 (Miami Dolphins, 48 (New England Patriots), 36 (New York Jets), 34 (Buffalo Bills)

Most Perfect Weeks in a season: 5 (1970 Miami Dolphins, 1976/2007 New England Patriots)

With recency bias clouding my judgment, I would have thought that the New England Patriots would have been the leaders in the Perfect Week department. However, after the early jump by the Joe Namath-led Jets of the late 1960s, the Miami Dolphins told the lead in the 1970s and have never looked back. Bill Belichick is looking to narrow the gap to the Dolphins, a gap that sits at a full ten weeks as of the end of the 2020 season.

AFC South (2002 - 2020)


Number of Seasons: 19

Perfect Weeks: 24 (Indianapolis Colts), 13 (Houston Texans, Jacksonville Jaguars), 12 (Tennessee Titans)

Most Perfect Weeks in a season: 4 (2013/2014 Indianapolis Colts)

Peyton Manning and Andrew Luck really didn’t leave the rest of the AFC South any chance. While this is the youngest division, as the Houston Texans entered the picture in the 2002 season, already the Indianapolis Colts have put up a double-digit lead in the Perfect Week category. The rest of the division – step it up!

AFC West (1960 - 2020)

Number of Seasons: 61

Perfect Weeks: 46 (Denver Broncos), 44 (Los Angeles Chargers), 43 (Kansas City Chiefs), 33 (Las Vegas Raiders)

Most Perfect Weeks in a season: 4 (2012 Denver Broncos, 1962/2019 Kansas City Chiefs)

The AFC West is full of fierce rivalries, and this manifests itself in the close nature of the Perfect Week tally. From 1980 to 2010, all four teams were right in the thick of the race. With two Super Bowl appearances in the past decade, the Denver Broncos hold a small lead over the Los Angeles Chargers and the Kansas City Chiefs, the latter of which has made up significant group over the past several years.

Let’s normalize the number of Perfect Weeks using the number of weeks played based on the division in which each respective team in the AFC played. The Indianapolis Colts are by far and away at the top of the AFC with respect to Perfect Week rate at 7.43% – note that the New Orleans Saints lead the NFC at 6.58%. Perhaps the rate of the Colts’ Perfect Weeks relates to the somewhat lackluster play of their divisional rival Texans, Jaguars, and Titans. Unfortunately for the latter two teams, the entry of the Houston Texans to the NFL in 2002 just misses the excellent Jaguar and Titans teams of the late 1990s which surely would have boosted the Perfect Week tally for those two franchises.

In a standard (pre-2021) 16 game NFL season (17 weeks including bye week), four Perfect Weeks would correspond to a Perfect percentage of 23.6% while five Perfect Weeks would equate to a Perfect Percentage of 29.4%; note that an average NFL season for most teams equates to less than one Perfect Week per season!

A total of 19 of the 32 NFL teams have accumulated at least one season with four or more Perfect Weeks. Of these 19 teams, only four teams have a season with five Perfect Weeks to their name – the Carolina Panthers, Los Angeles Rams, Miami Dolphins, and the New England Patriots. In chronological order, here I present the teams with four or more Perfect Weeks along with details of how they fared in the postseason.

* Denotes a 14 game regular season

It’s actually quite interesting how different the division alignments were in the past, as some divisions had up to seven teams! The basis behind the Perfect Week analysis breaks down completely for the older teams; for example, the division that the 1964 Philadelphia Eagles played included the Cleveland Browns, St. Louis (Arizona) Cardinals, and Pittsburgh Steelers in addition to the expected NFC East rivals. Nevertheless, let’s continue on, as one can see how it would have been very difficult to run the analysis on the basis of historical divisions. Alternatively, I could have used the 2002 NFL division realignment for a common starting point across all divisions, but I wanted to capture all those pre-2000 seasons as well.

In terms of success of these teams that accumulated at least four Perfect Weeks, the majority of them fared quite well in the regular season, as 25 of 28 made it to the postseason, of which there was one AFL Champion and five Super Bowl Champions along with two NFL Championship runner-ups and two Super Bowl runner-ups.

As to the question of the greatest regular season with regards to number of Perfect Weeks – the honor falls to the 1976 New England Patriots, who claimed a total of five Perfect Weeks – using the tiebreaker of achieving this feat in only 14 regular season games!



While tracking Perfect Weeks does not mean much of anything at all in the grand scheme of franchise glory, as achieving a Perfect Week is entirely dependent on the follies of at least two other division rivals, it is quite fun to see how it all plays out – and it is especially satisfying seeing the Packers at the top of the NFC North cumulative standings!