Football has changed over time and in the last couple of years more and more money is involved in the game, through various sponsorship deals, big rises in terms of prize money etc. With the increase of money flow revenues of clubs have also seen a natural rise.
Calcio Finanza published revenue data about several clubs across Europe and the numbers show that Manchester City is on top of the list in terms of revenue increase from 1994 to 2018. Generally, English clubs have done well in the last 24 years but even some Italian clubs like Juventus or Inter have grown significantly. On the other hand, there is AC Milan with the lowest increase: just 74% from their glory days in the 90s.