The summer transfer window threw up a few surprises and plenty of money was splashed, but which clubs were the smartest and who got the best deals?
According to findings from this summer's moves, Arsenal might have overpaid for Nicolas Pepe, Everton should have got more for Idrissa Gueye and a newly promoted team got the bargain of the window.
How does it work?
Carteret Analytics use their system to advise seven clubs in England's top two tiers as well as 12 leading clubs from Europe and the rest of the world.
The data center on the 'intrinsic value' of a player - a calculated fee based on performances for the selling club and the projected impact on the buying club, as well as taking into consideration their prime age (usually 26-30).
This is essentially the monetary value of the player's contribution to winning football matches and how influential he is to creating and preventing goal-scoring opportunities.
By assessing the intrinsic value, clubs can determine how much money they want to receive for a player and likewise, how much they are willing to spend on any new players.
Have Arsenal carried out bad business?
Arsenal took center stage on transfer deadline day - selling forward Alex Iwobi to Everton and bringing in Chelsea center-back David Luiz and Celtic full-back Kieran Tierney. But how did they end up in the 'bad business' category?
Iwobi's intrinsic value while at Arsenal went up to £46.26m but he was sold for just £27.36m, suggesting the sale was undervalued by almost £19m.
Arsenal signed Ivory Coast winger Nicolas Pepe from Lille for a club-record fee of £72m - a whopping £21.77m over his intrinsic value figure.
And they were sold short on teenage defender William Saliba from Saint-Etienne and let go of former captain Laurent Koscielny to Bordeaux for more than £20m under his projected fee.
But Arsenal did bring in cover for Koscielny at a good value. Chelsea's Luiz was rated at £34.8m but Unai Emery's team brought him in for just £7.8m - not bad for a Premier League and Champions League winner with years of experience in the English top flight.
Was Aaron Wan-Bissaka's transfer a fair one?
Everton raised eyebrows with their signing of 19-year-old forward Moise Kean from Italian champions Juventus. And they got a pretty fair deal, paying just £4m over his projected value, as well as fighting off competition from the likes of Borussia Dortmund.
They also did well to bring in Manchester City's Fabian Delph for under £9m. The versatile England international had a value of £54.58m to his selling club.
Midfielder Andre Gomes' permanent move from Barcelona cost just £22.5m too, a much lower fee than his intrinsic value to Everton. And of course, the signing of Arsenal's Iwobi was another good piece of business.
Shrewd business from Bournemouth and Wolves
The best business took place among clubs outside of the Premier League's top six.
As well as Crystal Palace impressing, last season's FA Cup semi-finalists Wolves were smart when signing loan players on permanent deals.
Mexican striker Raul Jimenez, who scored 15 goals in 37 games last season, was signed from Benfica for a club-record £34m - a good deal because his intrinsic value was rated at £43.37m.
Norwich bag a bargain, Spurs sell cheap
Premier League new boys Norwich City got the steal of the summer.
They bought Sam Byram from West Ham for just £747,000. He was valued at £27.7m by the selling club but is significantly lower for Norwich at £7m. They have still secured a player with Premier League experience for just over 10% of his monetary value though.
And at Leicester, they bagged a good deal for Newcastle's Ayoze Perez. The 26-year-old was sold for £13m less than his intrinsic value for the Foxes.
So who got ripped off? Well, Tottenham sold defender Kieran Trippier to Atletico Madrid at an undervalue of over £40m.