How is the cap number for each year determined?

The cap number for each year is determined by adding the signing bonus proration back to the player's base salary for that specific year. This is important because the signing bonus is often spread out over the duration of the contract for salary cap purposes.

When a player signs a contract that includes a signing bonus, that bonus is typically prorated over the life of the contract. For instance, if a player receives a $10 million signing bonus on a four-year deal, $2.5 million of that signing bonus would count against each of the four years' salary caps.

Thus, adding this prorated portion of the signing bonus to the base salary for that year gives you the total cap number, which reflects the real cost that the player represents to the team’s salary cap in that season. This approach ensures that teams account for bonuses fairly over the life of the contract, rather than taking the entire signing bonus hit in the year it was signed.

Base salaries and bonuses (excluding the signing bonus) are also components of a player's compensation but do not alone determine the cap figure for the year. The signing bonus, being prorated, is a crucial part of this calculation in calculating the cap number each year accurately.