1. A method performed by a computer device, the method comprising: defining a common abstract class associated with performing a plurality of financial calculations associated with a plurality of programs having a common object oriented architecture, the defining the common abstract class being performed by the computer device; defining an instrument class within the common abstract class, the instruments class comprising a plurality of equity, debt, or derivatives instruments arranged in a hierarchical manner, the defining the instrument class being performed by the computer device; defining a models class within the common abstract class, the models class comprising one or more objects or functions used by the plurality of programs to perform the plurality of financial calculations, the defining the models class being performed by the computer device; providing an input mechanism through which a user can provide one or more parameters to at least one of the one or more objects or functions, the providing being performed by the computer device; performing a financial calculation based on the one or more parameters provided via the input mechanism, the performing being performed by the computer device; and outputting a result of the financial calculation, the outputting being performed by the computer device.