As we defined them in the Background section, events are external happenings that an entity must react to but that are not controlled by the entity (see Figure 1.4).
Figure 1.4 Systems in the trading markets must handle events occurring outside the firm that affect accounts and holdings.
When money is put into an account or paid out, the overall value of the portfolio changes by the amount of the infusion or payment, changing the overall value of the portfolio. Less commonly, assets can be contributed to a portfolio or removed from the portfolio directly. These are the only types of transactions that change the value of a portfolio ...