Liverpool have been able to enjoy huge success in recent years whilst balancing the books, as have Bayern Munich, but the likes of Manchester United - and now Barcelona - have spent huge amounts and must now rebuild their squads

Net spend has become the new favourite phrase when it comes to transfer activity - a way of keeping a sense of perspective.

Some clubs have thrown money at players in pursuit of glory, although not all have found it. The likes of Manchester United, their neighbours Manchester City and PSG have all invested huge amounts with little regard for the balance sheet, knowing full well they have it to spend.

Others have had to be more measured. A one in, one out type approach. In the eyes of some, that makes their investment all the more impressive given they had to, more or less, spend what they make, or at least keep those two numbers relatively close.

Liverpool have championed that with some of their transfer dealings highlighting how to build a playing squad within a financial structure. The sale of Philippe Coutinho wasn't the loss of a star player, it was seen as an opportunity to invest in areas that needed addressing.

Virgil van Dijk, Alisson and co all moved to Anfield and the rest, as they say, is history. Some of their domestic rivals, namely the Red Devils, had spent with little long-term planning in mind. The same could be said of Barcelona - whose transfer activity has left them with huge debts.

The CIES Football Observatory has recorded the net spends of clubs across Europe since the 2012/13 season. The world record transfer fee has been smashed in that time thanks to Neymar's switch from Barcelona to Paris with player values inflating at a rapid rate. We take a look at the top 25 net spenders of the last ten years, which highlights the success of some clubs and exposes the flaws of others.

Ed Woodward has signed off on several failed transfers at Man Utd.

1. Man Utd -€1,075bn
So much spent and so little to show for it. Since the summer of 2012 United have won just one Premier League title and have failed to challenge since. Millions and millions have been spent on big names in an effort to restore success to Old Trafford, but the likes of Angel di Maria, Romelu Lukaku and Harry Maguire have been unable to make the desired impact.

2. Man City -€984m
They've invested huge sums, but they've certainly had a return on investment. The Abu Dhabi wealth has transformed the Etihad outfit and in the past decade they've won 11 domestic honours thanks to the talents of Kevin De Bruyne, Rodri and Ruben Dias whilst a club-record fee was recently spent on Jack Grealish.

3. PSG -€941m
Like City, the Parisians have been funded the wealth from the Middle East, in this case Qatar. Their millions have allowed PSG to dominate domestically, although their much craved Champions League title has eluded them. Signings of Neymar and Kylian Mbappe have helped make the club a global brand.

PSG broke the transfer record to sign Neymar in 2017.

4. Barcelona -€650m
The Catalans haven't been without success in the past decade, but a lack of forward planing leaves them needing a rebuild. Their mammoth net spend figure comes despite receiving £198m for Neymar, but investments in Ousmane Dembele, Antoine Griezmann and Coutinho have not worked.

5. Arsenal -€583m
Almost €600m spent and the club have just four FA Cups to show for it. No longer regulars in the Champions League, the north Londoners have let the likes of Mesut Ozil and Pierre-Emerick Aubameyang leave for nothing. Club-record signing Nicolas Pepe is now a squad player with major investment still needed at the Emirates.

6. Juventus -€561m
The Old Lady increased their spending in the second half of the decade as they desperately tried to land Champions League success. A club-record fee was spent on Cristiano Ronaldo, ultimately a failed project. Other notable arrivals include Mattijs de Ligt and Dusan Vlahovic with the Italians now in the midst of a rebuild.

Cristiano Ronaldo moved to Turin but couldn't deliver European glory.

7. AC Milan -€432m
The biggest spenders on the list who've yet to win a trophy in the past decade. Once a European superpower, the Rossoneri are attempting to get back to their previous stature. Leonardo Bonucci was signed for a club record fee, and then sold back to Juventus a year later. Lucas Paquetá and Andre Silva both cost north of €30m and have also left the San Siro.

8. Everton -€429m
Farhad Moshiri's millions have been pumped into the Toffees and yet they find themselves fighting for Premier League survival. Big money has been spent on the likes of Jordan Pickford and Richarlison but the club are in major need of an overhaul with many of their players underperforming.

9. Aston Villa -€424m
The sale of Grealish in the summer makes their figure look a lot different. The Midlands outfit have been relegated and promoted in the past decade and wasted no time in investing huge sums to retain their Premier League status. Over £100m was spent following their return and their spending hasn't slowed down since.

10. Chelsea -€413m
The Blues once upon a time would've topped this list, but they are now a more settled squad who require steady investment rather the activity we saw back when Roman Abramovich arrived. Lukaku was signed for a club-record fee in the summer but sales of Eden Hazard, Diego Costa and Oscar have levelled the scales.

11. Inter Milan -€385m
The Italian club finally claimed a first Serie A title since Jose Mourinho last season thanks to Antonio Conte. He was allowed to bring in the likes of Lukaku for big money, although the club have since made a profit on the Belgian. Achraf Hakimi was another notable investment who has also been sold for a profit.

12. West Ham -€374m
Their current success is by no means down to large sums being spent, if anything a more measured approach has been more rewarding. It was during Manuel Pellegrini's tenure that big money was spent on the likes of Felipe Anderson - who failed to make the grade - whilst Sebastian Haller was a failed recruit.

13. Bayern Munich -€363m
The most successful outfit on the list and yet they've spent less than some clubs who've yet to win a trophy. Bayern have claimed two trebles in the last decade with Robert Lewandowski, their main man, joining on a free. They've also exercised the market impressively by signing the likes of Serge Gnabry for €8m.

14. Liverpool -€347m
A masterclass from Jurgen Klopp. Take one look at the team he inherited in 2015 and the one he works with now and it's scarcely believable. Coutinho's sale was a real catalyst whilst the club have continued to sell players for notable fees, and in some cases for profit whilst adding world class talent for what would be deemed modest fees.

15. Newcastle -€339m
This number could be about to get a lot worse following their takeover by a Saudi consortium. Big sums were invested in January to ensure survival and the Magpies are set to go again in the summer. Bruno Guimaraes and Chris Wood were signed for more than £60m with big names expected in the coming months.

Newcastle's spending is set to increase massively due to the funds now available to Eddie Howe

16. Tottenham -€336m
Daniel Levy has had control of the purse strings for a long time and his inability to loosen them may have cost the north Londoners. Now they are in the midst of a rebuild, the unfortunate thing for them is that big money signings haven't worked thus far, Tanguy Ndombele perhaps the biggest flop.

17. Crystal Palace - €292m
The Eagles have spent the last decade in the top flight and have invested steadily to ensure they remain in the Premier League. Patrick Vieira conducted the biggest squad overhaul in years back in the summer. Whilst Christian Benteke and Mamdou Sakho, both signed from Liverpool, are the club's record arrivals.

18. Leicester City -€275m
The Foxes have been promoted and claimed Premier League glory over the past decade and continue to invest shrewdly, both on and off the pitch. They have narrowly missed out on the top four in recent years but many of their signings have been successes, namely Youri Tielemans and Wesley Fofana whilst the exit of Maguire helped keep their finances steady.

Harry Maguire's move to Manchester helped balance Leicester City's finances

19. Brighton -€248m
Another club to rise through the ranks and are now enjoying a fifth season in the top flight. Brighton offloaded academy graduate Ben White for £50m in the summer and have been smart with their buys. Adam Webster was signed from Bristol City and is a regular whilst Yves Bissouma looks a bargain at £15m.

20. Wolves -€247m
The Molineux outfit have benefitted massively from their takeover back in 2016, spending big when they were a Championship side. They've continued to invest shrewdly and have been able to sell players on for big profits, most obviously Diogo Jota, but that hasn't halted their development.

21. Napoli -€228m
Italy's top flight title continued to elude Diego Maradona's former side, who have two Coppa Italias to their name in recent years. They've seen players come and go, making a huge profit on Gonzalo Higuain back in 2016. Edinson Cavani was also a big money departure.

22. Wolfsburg -€190m
The German side enjoyed an excellent year in 2015 with De Bruyne a driving force before he was sold to City. Julian Draxler has also arrived and since departed, although they made a loss on the German. Much of their spending has been incremental, rather than on big money buys.

23. RB Leipzig - €186m
Timo Werner, Naby Keita, Dayot Upamecano and Ibrahima Konate have all left for big fees as the Red Bull-owned signed continue to work with a model that allows them to offload their best players for big fees. That doesn't stop them investing though with hefty amounts spent on the likes of Dani Olmo and Angelino.

24. Leeds -€181m
After more than 15 years away the Whites returned to the Premier League in 2020 and have set about investing to keep them in the top flight. For years Leeds hardly spent a thing as they battled financial issues, but now the likes of Raphinha and Diego Llorente are among their big buys.

25. Real Madrid -€179m
Incredibly Los Blancos, the club who seemingly pioneered big spending, are incredibly low down on the list. Without a Galactico for years - something that has angered supporters. Ronaldo was sold for a profit back in 2018 but a stadium redevelopment has hampered spending, hence their desire to lead the failed Super League project.