The NFL Draft trade value chart technically was Johnson’s idea, as he and team owner Jerry Jones wanted to assign numerical values to draft picks in order to make more clear the viability of trades. But they enlisted Mike McCoy, then a Cowboys minority owner, to create the chart.

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“Jerry and Jimmy both liked to trade from Day 1,” McCoy told the Fort Worth Star-Telegram in 2007. “I was always in the draft meetings. So I said I would give it a try. It took only two days and a few tries. I started out with the basic assumption that a second-round pick is worth two third-round picks. That was the rule of thumb that owners and coaches used for a long time. It wasn’t hard once you figured out how to do it.”

Added Jones: “He thought you could quantify something that was not numerical just on the face on it. That’s a value of trade, and anybody that has ever been around Mike McCoy knows that he is a genius when it comes to his being able to work with numbers. The engineer in him makes him very practical, very practical, and so he was the perfect guy for the job.”

Almost 30 years later, NFL teams are still using a variation of the trade value chart the Cowboys created.

Variation is the key word, because teams now used a revised version of the chart to account for the ability to trade compensatory picks (which was not allowed in the early 1990s), the rookie wage scale and a bigger sample size of the success of draft picks.

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As Patriots coach Bill Belichick explained prior to last year’s NFL Draft, teams used to argue about whose chart was more accurate when discussing trades. For the most part, that’s no longer the case.

“I would say that, in general, the trades over the last several years for the most part have been, let’s call them within five to 10 percent, pretty equitable trades,” Belichick said (via Pro Football Talk). “So, for you to have a chart that’s different than the other 31 charts isn’t really that productive because now we’re just arguing about which chart — ‘My chart says this. Your chart says that.’

“I would say everybody probably uses about the same value chart. I’d say in our draft trade negotiations through the years, especially the last two or three years, there hasn’t been a lot of, ‘My chart says this. Your chart says that.’ Now, 10 or 15 years ago there was some of that. ‘Oh, here’s what we think it should be.’ Well, the other team’s in a different ballpark because they’re looking at a different chart.”

Below are a couple examples of current NFL Draft trade value charts, starting with the model Johnson McCoy created.

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NFL Draft trade value chart (Jimmy Johnson)

Below is the 2020 NFL Draft value chart based on what has become known as the Jimmy Johnson model. Because teams were not able to deal compensatory draft picks when the model was created in the early 1990s, it includes only 224 of the now-customary 256 draft picks.

(Included are the teams that entered the 2020 NFL Draft with each pick.)

NFL Draft trade value chart (Over The Cap)

A few years ago, OverTheCap.com’s Jason Fitzgerald and Brad Spielberger built an updated NFL Draft trade value chart to account not only for the addition of compensatory draft picks, but also the context of rookie contract salaries.

Below is the chart they created, followed by their process and reasoning.

From Over The Cap:

“First, we found the average of the top five average per year (APY) contracts at each position in each year. For example, the top five QB APYs are $35 million, $34 million, $33.5 million, $33.5 million, $32 million. The average of these five APYs is $33.6 million. An APY of $16.8 million would thus be 50 percent of top five APY. We then converted every new contract in each year into a percent of the top 5 APY average at the respective position.

“In order to get a more accurate representation of the expected performance of a particular draft pick and increase the sample size, we smoothed the data by averaging out the post rookie-contract APY amounts for a few picks before and after each draft pick. The grouping of a few draft picks within a small range removed a lot of the variance that occurs in large part due to “busts” and generated more realistic projections, as the range more accurately reflects the quality of talent available to a drafting team.

“The ranges start very small (e.g. examining picks No. 1 & No. 2 for the No. 1 slot) and expand in the later rounds of the draft.”