As we enter the final couple of weeks of the summer transfer window, sides around Europe are working feverishly to bring in new recruits to strengthen their ranks for the 2022/23 season.

Already this summer, per Transfermarkt, a total of nine players have moved clubs for fees in excess of £50 million, including Darwin Nunez's switch from Benfica to Liverpool and Marc Cucurella trading Brighton for Chelsea.

The ever-spiralling nature of transfer fees means that few fans bat an eyelid when the £50m barrier is broken these days.

However, it was only back in 2009 that Kaka became the first £50m player when he joined Real Madrid from AC Milan for £56m.

Some 13 years later, the evolution of football finances means the world record transfer fee now stands at £199.8m that Paris Saint-Germain paid Barcelona for Neymar in 2017.

Recently, Transfermarkt uploaded a live graphic charting the crazy inflation levels in the transfer market since 1990.

Quiz: Can you guess the player from their Wikipedia career path?

Back 32 years ago, it was Roberto Baggio who held the world record transfer for his £8m move from Fiorentina to Juventus.

To put that into perspective, PSG could almost have purchased Baggio 25 times for the £199.8m they paid for Neymar.

In total, 14 players have held the title of the world's most expensive player other than Baggio and Neymar.

Neymar celebrates at PSG

PARIS, FRANCE - OCTOBER 31: Neymar of PSG celebrates after his free kick leads to the goal scored by Layvin Kurzawa of PSG during the UEFA Champions League group B match between Paris Saint-Germain and RSC Anderlecht at Parc des Princes on October 31, 2017 in Paris, France. (Photo by Dean Mouhtaropoulos/Getty Images)

Some were worth every penny, winning Ballon d'Or honours and becoming club legends. For others, though, it simply didn't work out.

Real Betis probably didn't expect to be relegated two years after splashing out a record £21.5m on Brazilian playmaker Denilson in 1998 and the less said about Paul Pogba's 2016 switch from Juventus to Manchester United the better.

Zinedine Zidane and Cristiano Ronaldo were both record-breaking signings for Real Madrid, but both repaid their mammoth transfer fees and then some.

Zidane delivered La Liga and Champions League success for Los Blancos as a player, before later taking over as boss at the Bernabeu and lifting even more silverware.

Cristiano Ronaldo unveiled as a Real Madrid player

MADRID, SPAIN - JULY 06: New Real Madrid player Cristiano Ronaldo is presented to a full house at the Santiago Bernabeu stadium on July 6, 2009 in Madrid, Spain. (Photo by Denis Doyle/Getty Images)

Following his £86.4m move from Manchester United in 2009, Ronaldo scored 450 goals in 438 appearances for Real.

So prolific was the five-time Ballon d'Or winner that the club were even able to sell him on at a profit to Juventus nine years later.

You can check out Transfermarkt's live graphic illustrating the wild inflation in the market over the last 30 years below.

Watch: The crazy rise of the world transfer record since 1990

The big question now is just how long we will have to wait for the first player to break the £200m mark in terms of a transfer fee.

Kylian Mbappe and Erling Haaland could both have smashed that milestone earlier this summer under different circumstances.

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Mbappe snubbed a big-money move to Real Madrid in favour of signing an insane new deal with PSG, while Haaland had a clause in his Borussia Dortmund contract which allowed him to leave for £54m - some £81m less than his market value.

That £200m signing is coming, though. As the last 32 years have shown, fees only tend to head in one direction.