Special Operations; Financial Functions - HP -80 Owner's Handbook Manual

Special Operations
If you followed instructions and read the Introduction, you have already
seen a typical example of the scope and power of the HP-80. Just in
case you're underwhelmed , and still think it's just another calculator,
here's an additional example: Suppose you invested $50,000 and were
guaranteed a return
of $10,000
each year for seven years. Now, try to
figure the annual rate of return by some ordinary method. Then do it
on the HP-80 as follows,
Enter: See Displayed:
711
1 000011 5 0000
I I . - _
% annual rate
of return
If you want to verify this
problem,
Enter:
STO
See Displayed:
711
RCL
. 1 0 0 0 0 1 1 1 1 - $ • • •
present value
The HP-80 has built-in logic that enables you to perform two broad
classes of complex functions:
(1)
financial and (2) interactive.
Certain keys are used to perform these special functions. Some
functions use keys from both the financial and interactive classifications
-as well as keys from the basic classification. For example, discounted
cash flow analysis and accumulated interest problems use both financial
and interactive keys.
Financial Functions
Financial functions are used primarily in investment and loan applica-
tions (simple interest, compound interest, annuities and bond prob-
lems). These problems require three known values to get a fourth value.
After each value is entered, it is loaded by pressing the applicable top-
row key that identifies the value. The fourth value is obtained by press-
ing the top-row key representing the unknown value. Interest is always
an annual rate unless specified to the contrary.
The key set associated with these functions is illustrated in Fig. 2. (note
that
SAV E
+ is not used to load values). You'll probably be surprised to
learn that the five keys in Figure 2 represent 17 functions and replace
all the compound interest, discount, bond and annuity tables commonly
in use.
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