A long thread on the Bundesliga Tax- the idea that there would be a big drop off in production from attackers when going from the Bundesliga to the Prem- with a consideration of the potential big Bundesliga transfers and their situations.

To consider this idea I've looked at every attacking player signed by Prem clubs from the Bundesliga for more than £15m pounds. This ends up being quite a small list- just 11 players.

It's worth noting that I've included De Bruyne and omitted Andre Schurrle. The former is a midfielder but I thought his G+A was relevant and the latter doesn't have good data availability xG wise from his pre Chelsea time.

Looking at their goals per 90, expected goals per 90, assists per 90 and expected assists per 90, it's clear that there is an overall trend of declining performance when moving from the Prem to the Bundesliga, but it is not as big as I had expected.

On average, when in the Bundesliga these players scored 0.44 G/90, which dropped to only 0.4 G/90 in the PL. This would equate to an average 'goal tax' of only 0.91, far better than the expected halving that people talk about when discussing major Bundesliga goal numbers.

Assist numbers, however, take a bigger hit. The players in the sample average 0.29 A/90 which dropped quite significantly to 0.19 A/90 in the PL. This is a little surprising but perhaps it reflects worse defending in that teammates can more reliably score?

Interestingly, xG/90 declines far more when moving from the Bundesliga to the PL than G/90 does, with the players getting 0.43 xG/90 in the Bundesliga but only 0.34/90 in the Prem.

This is where you can see the truth in the idea of a tax- the attackers did not get the same number of high quality chances after their move. Despite this, their goals were relatively stable as they on average became better finishers with better goal to expected goal ratios:

Considering the average age of the transfers 24- this improvement in finishing makes sense in terms of player development. The overall picture for each player can be seen in this slightly confusing graph:

So overall, unsurprisingly, players produce less in terms of G+A per 90 on average when moving from the German top division to the English one. Removing xG data, the trends for each player is as such:

Drops in A/90 are extremely common, and that would be the main thing I'd point towards when projecting numbers for these new transfers. Only 2 players improved in both G/90 and Assits/90- Son and Dzeko. Some- Firmino, Yarmolenko and Pulisic improved their G/90 numbers though.

I'd now like to discuss this in the context of Werner, Sancho and Havertz. Firstly, I'd say both Werner and Sancho are in situations that are extremely friendly to their G+A numbers.

Werner is playing as the main forward under Nagelsmann's very well coached Leipzig side and has seen his xG/90 have a huge jump from 0.55 the three seasons prior to 0.79 this season. That is a big, big xG/90 figure that he will likely not see wherever he goes next year.

It's also worth noting that easily the biggest flop in the list examined was Joelinton, a player that went from being the primary forward in a Naglesmann team to a situation at Newcastle where he had far less xG/90.

I do think that Werner would adapt much better than Joelinton. Firstly, he is a better player, Joelinton underperformed his xG at Hoffenheim and Werner is really over performing his now. Werner is also likely to go to a much better situation obviously.

It's also worth noting that the ratio of goals to expected goals is a good proxy for finishing ability that remains relatively stable when making the switch to the Prem (and indeed usually improves) which gives a lot of encouragement re Werner.

I wouldn't expect him to produce to the same amount he is now (0.97 G/90 is crazy) but I'd expect a similar regression pattern to Auba, who has definitely been a successful signing. Werner is also younger at the time of his expected move giving him more time to develop.

Moving on to Sancho, I would expect his assist numbers to fall big time upon moving to the PL. The 'tax' for assists is already bigger in transfers and he's massively over performing his xA now (0.37 xA/90 to 0.6 A/90). He has really benefited from very clinical teammates.

In terms of goals, Sancho is clearly an outstanding finisher, his goal to xG ratio is nearly as good as Son's was in the Bundesliga, which is something that has remained extremely good in the Prem. I'd expect his goal numbers to be very similar actually, considering past trends.

Finally, I'd say Havertz benefits from Leverkusen's system less than Sancho and Werner benefit from their teams. He's also been a consistently good finisher but he has underperformed his xA this year. I'd expect him to adapt well to a move.

Overall, big money attacking signings have largely adapted very well to the Prem despite the perception of the Bundesliga, especially if they have gone to big six sides. There are exceptions of course, but on the whole I think the idea of a significant tax is overblown.

That was a long thread- if you got the bottom, thanks for reading. Thinking about doing the Championship next, then maybe the other top 5 leagues. Let me know what you think.