Your goal as a football manager is to deliver success on the pitch, but you must be mindful of the fact that football is a business. The chairman must ensure the club continues to make money and is a commercially viable concern, so he'll be partially judging you on how well you stick to budgets. You can use these finance screens to asses the commercial success of your stewardship and see the impact of new signings on your revenue, for instance.
The finance screen breaks down into five options to aid your understanding of the figures: Summary, Income, Expenditure, Transfers and Salary.

Summary
This overview explains the basic financial status of the club. For most managers this will be all you need to know in order to operate as boss, from a financial perspective. The remaining transfer budget shows how much money you have left to use to acquire players. If you think you need more you can approach your chairman with a request for extra funds (see the Make Board Request on the Confidence screen).
The percentage of transfer funds made available explains how much of the revenue you generate from selling players will be made available for buying replacements. A club with healthy finances and a generous chairman will be quick to make a large amount of the cash recouped available for you to spend. Bear this figure in mind when you look to raise cash to acquire a player that is out of your price range.

Income
A self-explanatory breakdown of the money coming into your club, the income screen is nevertheless useful for seeing the impact of new signings and success on the pitch. Expect a big name player acquisition to boost revenue from merchandise, and on-field success to help raise match day income and gate receipts in the short term as well as season ticket sales in the long term.

Expenditure
As a manager you have far more control over spending than income, which is handled by behind-the-scenes marketing men, executives and your chairman. Players Bought is likely to represent the biggest slice of expenditure at many clubs, though almost every team can expect to have a large wage bill. Of course this can be managed by carefully assessing the deals you offer to players.

Transfers
A brief rundown of the cost of each transfer you have made, along with any contract clauses that you should consider when weighing up your future finances.

Salary
Over the last couple of decades, player salaries have grown hugely across the board. With this in mind many clubs have adopted a wage structure that is designed to keep wages to a manageable level. In Football Manager, this structure is represented with an overall wage budget, which is not totally fixed, but which you should pay great heed to if you aren't to be seen as financially wasteful by your chairman.
The main part of this screen shows you a more precise breakdown of the wage structure of your club. The chairman allocates salary funds according to how important you deem a player to be. To circumvent the wage cap for a rotation player, for instance, you could offer a player (see Make Offer) a First Team role. The danger with this, however, is that your player will expect to figure in most first team games and will become disillusioned if this is not the case.