For most of baseball, it’s All-Star Week, a time where we celebrate the best players in the game by letting them strike out against guys throwing 100 mph for 20 pitches at a time. At FanGraphs, though, All-Star Week means something else; it’s time for the annual Trade Value series.

While it’s almost always an academic pursuit, given that most of these guys are practically unavailable in trade, it’s still fun to work through the various pros and cons of the game’s most valuable players. We’re kicking off the series with the introduction post today, which includes a look back at guys who aren’t carrying over from last year’s list, and will have the honorable mentions and the last 10 guys in tomorrow. We’ll do 10 spots per day, culminating with the top 10 on Friday.

I’ve been doing a list like this for 12 years now, with the first one coming way back in 2005, and I moved the exercise to FanGraphs in 2008. The process has changed over the years, and hopefully the information presented gets a little better each year. As with last year, Dan Szymborski has been kind enough to provide five year ZIPS forecasts for every player on the list, so you will be able see how his algorithm projects each player from 2017 through 2021. The players aren’t ranked based on those projections, but I think that piece of information provides some insight into how the long-term value of various players might compare to each other. We’re also displaying the contract status for each player, which is, of course, a major factor in determining their trade value.

For those new to the series, the list is an attempt to answer the question of who would bring back the most in trade for their team if they were to be put on the market and made available before the deadline. Because different teams have varying resources and roster needs, we’re not saying that if one player is ranked ahead of another player, the team with the lower ranked player would make a one-for-one swap for the higher ranked player; there are some teams that will put more of a premium on short-term value while others who are looking to maximize long-term potential, and salary is a larger factor for some organizations than others. Of course, every team would love to have a player who contributes both now and in the future, and does so without consuming a large part of their budget; guys who check all of those boxes will rank at the very top of the list.

For most players that we’ll discuss over the next week, though, they come with a combination of those features, but don’t check all those boxes. Weighing the pros and cons of their ability to help a team win right now, their place as a long-term building block, and how their salary plays into a team’s financial picture requires balancing different strengths and weaknesses, but there’s no question that the game has shifted towards younger players over the last few years, and teams have never put a higher price on youth than they do today. As such, this list is also going to skew younger than it has in most years, as teams have started to shy away from moving their best young talents, realizing that in many cases, the young guys — especially the ones close to the big leagues — are nearly as capable of helping a team today as “proven” older players.

And right now, we have a flood of great young talent pouring into baseball. Especially at shortstop, there’s a depth of talent perhaps never before seen, but at most every position, there are a host of terrific young players looking like they’re the future of the game. That wave of great young talent means that, with only 50 spots on the list, we’re simply not going to be able to include everyone, and many of the biggest name players in the game today have been pushed off the list in favor of the next generation, especially as these big name guys start to decline and get expensive at the same time. And, of course, it’s natural for players to lose trade value each year, as they march closer to free agency; some players just happen to lose value a little faster than others.

So, before we start to unveil the list, let’s talk about the players who made the cut last year but fell off the list this year.

For most of those guys, their performance since the list was published last year simply hasn’t lived up to what they did previously, and they’ve eroded some of the league’s faith in their abilities to still perform at an elite level. McCutchen takes the biggest fall, but that is because, in addition to his 2016 struggles, he’s also now only two years away from free agency; he was going to drop significantly in the rankings even if he kept playing well, so his struggles have just compounded the slide. This doesn’t mean McCutchen is no longer a valuable trade chip, but that the Pirates probably wouldn’t get the same kind of haul for him that one might expect for a guy who has been an elite performer.

Stanton takes a big fall not only because his contact rates have raised some concerns about his long-term value this year, but because those concerns make it less likely that he’ll exercise the opt-out clause in his contract, which would void the final seven years of his deal. With that likelihood reduced, the full weight of his contract would likely scare off many suitors, and while a few teams would still happily trade for him, there probably wouldn’t be enough demand to take on the contract for the Marlins to also extract a big return in talent.

Gray leads the group of young pitchers who have regressed in 2016, with Harvey, Wacha, Ventura, and Keuchel also going the wrong way this year. With the exception of Angry Yordano, they’d certainly still be sought after in trade if they were made available at the deadline, but the prices on each have diminished significantly with their struggles and their closer proximity to arbitration and free agency.

Two guys from last year’s list were actually traded since the list was published, and in both cases, they went cheap relative to expectations; Simmons and Frazier both are off the list after MLB teams showed us exactly what their trade value really was. Frazier would have fallen off the list anyway, since he was getting close to free agency, and with teams moving towards youth over short-term veterans, he probably shouldn’t have made the cut a year ago. Simmons is a reminder that teams still don’t pay for defense the same way they pay for offense, and that defensive specialists aren’t going to bring back in trade what we might think based on their production.

Buxton and Soler are reminders that not every talented young player improves linearly, and while both could still have good careers, it seems pretty clear that the stock of both players is down relative to what it was a year ago. But in talking with people in the game, no one is taking their foot off the young player pedal, and even with those two falling off the list this year, you’re still going to see a lot of unproven guys on the list this year; teams are willing to take that risk to get a franchise young player.

Rendon, Puig, and Abreu have all ranked quite highly on this list at various times over the last few years, but each of them now look like they peaked early. If Buxton and Soler are reminders that prospects are no sure thing, these three serve as reminders that no one is a sure thing, even guys who look like MVP candidates early in their careers.

And then there are the guys who haven’t really lost value in terms of expected performance, but are simply moving down at the natural pace due to their march towards their more expensive years. Freeman is still a good player on a below-market contract, but he’s in the last of his super cheap years, and is set to make $17 million next season, so he’s not quite the bargain he was in past years. Panik remains a quality performer with a very interesting set of skills, but he’s used up one of his pre-arb years this year, so there’s less value to trade than there was last year; he now finds himself getting passed by a few of the elite young guys making their way up the ladder.

So those are the guys who won’t be coming back to the list after appearing last year. Tomorrow morning, we’ll cover the players who just missed the cut, and then we’ll publish #50 to #41 in the late-morning, kicking off the series in earnest. I hope you find this exercise as fun as I do, and enjoy a week of thinking about the trade value of guys who almost certainly won’t be traded.