Section 3: Basic Financial Functions 37
Suppose you deposited (paid out) $1,000 into an account that pays 6% annual 
interest and is compounded monthly, and you subsequently deposited an 
additional $50 at the end of each month for the next 2 years. The cash flow 
diagram describing the problem would look like this:
The arrow pointing up at the right of the diagram indicates that money is 
received at the end of the transaction. Every completed cash flow diagram must 
include at least one cash flow in each direction. Note that cash flows 
corresponding to the accrual of interest are not represented by arrows in the cash 
flow diagram.
The quantities in the problem that correspond to the first five keys on the top row 
of the keyboard are now readily apparent from the cash flow diagram.
z n is the number of compounding periods. This quantity can be expressed in 
years, months, days, or any other time unit, as long as the interest rate is 
expressed in terms of the same basic compounding period. In the problem 
illustrated in the cash flow diagram above, n = 2 × 12.
The form in which n is entered determines whether or not the calculator 
performs financial calculations in Odd-Period mode (as described on pages 
51 through 54). If n is a noninteger (that is, there is at least one nonzero 
digit to the right of the decimal point), calculations of i, PV, PMT, and FV 
are performed in Odd-Period mode.