Ryan Dempster entered the 2012 season in the final year of his contract. He was coming off season in which his ERA had ballooned to 4.80, but his FIP and xFIP were in line with what he'd done as a starter since 2008. His FIP was 3.91 and he had an xFIP of 3.70. The projections had him at a 3.92 FIP this year. The WAR projection was 2.4.
Berselius did using FIP and Fangraphs uses it to calculate WAR and so far this year he's been worth 1.7. Unlike last year, his ERA is significantly lower than his 3.26 FIP. He currently has the 4th best ERA in baseball, but he's not nearly that high in the FIP rankings. Still, Dempster has had a very good season, but it's been viewed as better than it really is thanks to the shiny ERA.
Dempster has apparently said he's willing to accept a trade so it's likely one will happen. There will be several interested teams, but he's making quite a bit of money and is owed $3 million in deferred money. I think we can assume the Cubs are on the hook for that no matter what so Dempster's salary this season is $14 million and that's what we want to focus on when trying to figure out his trade value.
There are 3 rest of season projections available: Oliver (The Hardball Times), ZiPS (available on Fangraphs), and PECOTA (Baseball Prospectus). Below is a table that averages the 3 projections.
From this point forward they're projecting 114 innings, a 4.00 ERA and a 3.82 FIP. I also included July 1st and August 1st as starting points to give us an idea of what his value may be depending on when he is traded. Currently we're expecting 1.7 additional WAR. That actually seems high to me. Oliver and PECOTA provide WAR projections, but ZiPS does not. Oliver gives Dempster 0.6 the rest of the way while PECOTA has him at 1.5. So keep that in mind. The 1.7 is a high estimate. Realistically it's probably closer to 1.2 or so, but you can see how that affects the trade value.
Even at 1.7 the rest of the year Dempster's surplus trade value is only $0.3 million. It's the same if he's traded in a couple weeks and only $0.2 million if he's traded at the end of July. So even if you estimate high you find he essentially has no trade value. This doesn't mean the Cubs won't get anything in return.
They could and probably will send the majority of the money he's owed to the team trading for him. Assuming this, if they traded him right now and sent $8.2 million they'd get back $8.5 million in value. In a couple weeks they'd get back $7.3 million and if they wait until the deadline only $4.8 million in return.
These farm system values were in 2009 so we should add some inflation, but it gives you an idea what the Cubs may be looking at for the return in a Dempster trade. I'll paste the most relevant information below:
|Top 10 hitting prospects||$36.5M|
|Top 11-25 hitters||$25.1|
|Top 26-50 hitters||$23.4|
|Top 51-75 hitters||$14.2|
|Top 76-100 hitters||$12.5|
|Top 10 pitching prospects||$15.2|
|Top 11-25 pitchers||$15.9|
|Top 26-50 pitchers||$15.9|
|Top 51-75 pitchers||$12.1|
|Top 76-100 pitchers||$9.8|
|Grade B pitchers (as graded by Sickels)||$7.3|
|Grade B hitters||$5.5|
|Grade C pitchers 22 or younger||$2.1|
|Grade C pitchers 23 or older||$1.5|
|Grade C hitters 22 or younger||$0.7|
|Grade C hitters 23 or older||$0.5|
The bolded red line is the maximum that we should expect the Cubs to get in return if they traded Dempster today. That's using the high WAR estimate so realistically it's probably closer to the Grade B pitcher or hitter. if they wait until the deadline the Cubs may be looking at only a grade C pitcher or a couple grade C hitters.
The Cubs farm system isn't going to improve much while trading Dempster. He's off to a great start, but it appears a lot better than it really is because his ERA is flashing in front of our eyes during every broadcast.