Texas Instruments TI-86 - ViewScreen Calculator Manual

TI-86 Financial Functions
Loading and Installing Finance Features on Your TI-86...............................2
Loading the Finance Features into TI-86 Memory..............................................................................2
Installing the Finance Features for Use...............................................................................................2
Displaying the FIN (Finance) Menu.....................................................................................................3
The FIN Menu.....................................................................................................................................3
Uninstalling the Finance Features.......................................................................................................3
Deleting the Finance Program from TI-86 Memory ............................................................................ 3
The TVM (Time-Value-of-Money) Variables................................................... 4
FIN VARS (Finance Variables) Menu...................................................................................................4
Setting the Payment Format........................................................................... 4
Payment Format Editor.......................................................................................................................4
Entering Cash Inflows and Cash Outflows..........................................................................................4
Using the TVM (Time-Value-of-Money) Solver..............................................5
FIN TVM Solver Menu.........................................................................................................................5
Solving for an Unknown TVM Variable (Payment Amount)................................................................5
Financing a Car...................................................................................................................................6
Computing Compound Interest...........................................................................................................6
Using the Financial Functions..........................................................................7
Entering Cash Inflows and Cash Outflows..........................................................................................7
FIN FUNC (Financial Functions) Menu................................................................................................7
Calculating Time-Value-of-Money......................................................................................................7
Calculating Cash Flows....................................................................................................................... 8
Calculating Amortization....................................................................................................................9
Amortization Example: Calculating an Outstanding Loan Balance...................................................10
Calculating Interest Conversion........................................................................................................11
Finding Days Between Dates............................................................................................................11
Defining the Payment Method..........................................................................................................11
Menu Map for Financial Functions ...............................................................12
MATH Menu (where FIN is automatically placed).............................................................................12
(MATH) FIN (Financial) Menu........................................................................................................... 12
FIN TVM (Time-Value-of-Money) Solver Menu.................................................................................12
FIN FUNC (Financial Functions) Menu..............................................................................................12
FIN VARS (Financial Variables) Menu...............................................................................................12
FIN FORMT (Financial Format) Menu................................................................................................12

Assembly Language Programming: Financial Functions
2
Loading and Installing Finance Features on Your TI-86
To load the financial features onto your TI-86, you need a computer and the TI-86
Graph Link software and cable. You also need to download the finance program
file from the Internet and save it on your computer.
Loading the Finance Features into TI-86 Memory
1 Start the TI-86 Graph Link on
your computer.
(WLink86.exe)
2 Turn on your TI-86 and display
the home screen.
^
-l
3 Click on the Send button on the
TI-86 Graph Link toolbar to
display the Send dialog box.
4 Specify the finance program file
as the file you want to send.
finance1.86g
5 Send the program to the TI-86.
The program and its associated
executable file become items on
the PRGM NAMES menu.
6 Exit Graph Link
Installing the Finance Features for Use
Use the assembly language program Finance to install the finance features directly
into the TI-86’s built-in functions and menus. After installation, the finance
features are available each time you turn on the calculator. You do not need to
reinstall them each time. When you run assembly language programs that do not
install themselves into the -Œ/menu, their features are lost when you
turn off the calculator.
All examples assume that Finance is the only assembly language program installed
on your TI-86. The position of FIN on the MATH menu may vary, depending on how
many other assembly language programs are installed.
1 Select Asm( from the CATALOG
to paste it to a blank line on the
home screen.
2 Select Financ from the PRGM
NAMES menu to paste Finance
to the home screen as an
argument.
-w&
#(move 4to
Asm( ) b
8&(select
Financ) E
3 Run the installation program.
Caution: If you have values
stored to variables used by the
finance features, they will be
overwritten. To save your
values, press *to exit and then
store them to different variables.
Then repeat this installation.
b
When sending a program
from your computer to the
TI-86, the calculator must no
t
be in Receive mode. The
Receive mode is used when
sending programs or data
from one calculator to
another.
The executable file
associated with the assembly
language program (
finexe
)
appears on the
PRGM
NAMES
menu, but you need
not do anything with it.
For assembly language
programs that must be
installed, up to three can be
installed at a time (although
the TI-86 can store as many
as permitted by memory). To
install a fourth, you must first
uninstall (page 3) one of the
others.
The variables that will be
overwritten are listed on the
FIN FUNC
and
FIN VARS
menus (page 12).

Assembly Language Programming: Financial Functions
3
4 Continue the installation. (Your
version number may differ from
the one shown in the example.)
&
5 Display the home screen. :
Displaying the FIN (Finance) Menu -Œ/
When you install the financial program on your TI-86 and activate it, FIN becomes
the last item on the MATH menu.
NUM PROB ANGLE HYP MISC 4INTER FIN
Finance Menu
The FIN Menu -Œ/'
TVM FUNC VARS FORMT Uninst
TVM Finance Uninstall
Solver Variables Menu Instruction
Financial Payment
Functions Menu Format Editor
Uninstalling the Finance Features
1 Display the FIN menu, and then
select Uninst.
-Œ/'
*
2 If you are sure you want to
uninstall, select Yes from the
confirmation menu. The FIN
menu is removed and the home
screen is displayed. (Your
version number may differ from
the one shown in the example.)
)
Deleting the Finance Program from TI-86 Memory
1 Select DELET from the MEM
menu.
-™'
2 Select PRGM from the MEM
DELET menu.
/*
3 Move the selection cursor to
Finance, and then delete it.
#(as needed)
b
4 Move the selection cursor to
finexec, and then delete it.
#(as needed)
b
If other assembly language
programs are installed,
FIN
may be in a menu cell other
than
-Œ/' .
When you uninstall the
finance features, the finance
assembly language program
s
(
Finance
and
finexec
) remain
in memory, but the
FIN optio
n
is removed from the MATH
menu.
Deleting the program does
not delete the variables
associated with the program.

Assembly Language Programming: Financial Functions
4
The TVM (Time-Value-of-Money) Variables
FIN VARS (Finance Variables) Menu -Œ/'(
TVM FUNC VARS FORMT Uninst
çI PV PMT FV 4PY CY
NNumber of payment periods FV Future value of loan or lease
IInterest rate (I%=)PY Payments per year (P/Y=)
PV Present value of loan or lease CY Compounding periods per year(C/Y=)
PMT Payment amount
♦ When you enter a value at prompts in the payment format editor (page 4) or
the TVM Solver (page 5), the corresponding variable values are updated.
♦ When you solve for a TVM variable using the TVM Solver, the corresponding
variable value is updated.
♦ When you enter numbers as arguments for a TVM function, the corresponding
variable values are not updated.
♦ When you solve for a TVM variable using a TVM function, the corresponding
variable value is not updated.
Setting the Payment Format
Payment Format Editor -Œ/')
TVM FUNC VARS FORMT Uninst
The payment format settings define the number
of payments per year (P/Y), the number of
compounding periods per year (C/Y), and
whether the payments are received at the end or
beginning of each period (PMT:END BEGIN).
The payment format editor to the right shows
the defaults. To change payments per year or compounding periods per year, enter a
new value. To change the payment due setting, move the cursor onto END or BEGIN,
and then press b.
Entering Cash Inflows and Cash Outflows
When using the financial functions, you must enter cash inflows (cash received) as
positive numbers and cash outflows (cash paid) as negative numbers. The financial
functions follow this convention when computing and displaying answers.
Prompts that correspond to
some TVM variables are
shown in parentheses.
You also can change a
setting by storing a value to
PY
or
CY
or by executing
pEnd
or
pBegin
(page 11).

Assembly Language Programming: Financial Functions
5
Using the TVM (Time-Value-of-Money) Solver
FIN TVM Solver Menu -Œ/'&
TVM FUNC VARS FORMT SOLVE
The TVM Solver displays prompts for the five
time-value-of-money (TVM) variables.
To solve for an unknown variable, enter the four
known variable values, move the cursor to the
unknown variable prompt, and then select SOLVE
(*) from the FIN TVM Solver menu. Values
displayed on the TVM Solver are stored to corresponding TVM variables.
Solving for an Unknown TVM Variable (Payment Amount)
You want to buy a $100,000 house with a 30-year mortgage. If the annual
percentage rate (APR) is 18%, what are the monthly payments?
1 Set the fixed-decimal mode to 2
decimal places to display all
numbers as dollars and cents.
-m#
"""b
2 Select FIN from the MATH menu
to display the FIN menu.
-Œ/'
3 Select FORMT from the FIN
menu to display the payment
format editor. Set 12 payments
per year, 12 compounding
periods per year, and payments
received at the end of each
payment period.
)12 #12 #
b
4 Display the TVM Solver and
enter the known values for four
TVM variables. The Nvalue of
360 was derived from 30 (years)
M12 (months).
&360 #18 #
100000 ##0
b
5 Move the cursor to the PMT
TVM variable.
$
6 Select SOLVE to compute the
answer. A small square is
displayed next to the solution
variable. The answer is stored to
the corresponding TVM variable.
*
When the TVM Solver is
displayed,
SOLVE
replaces
Uninst
on the
FIN
menu.
Enter cash inflows as positiv
e
numbers and cash outflows
as negative numbers.
You cannot leave a variable
blank. If you do not have a
value, set it to zero.

Assembly Language Programming: Financial Functions
6
Financing a Car
You have found a car you would like to buy. The car costs $9,000. You can afford
payments of $250 per month for four years. What annual percentage rate (APR)
will make it possible for you to afford the car?
1 Set the fixed-decimal mode to 2
decimal places to display all
numbers as dollars and cents.
-m#
"""b
2 Display the payment format
editor. Set payments per year
and compounding periods per
year to 12. Set payment due at
the end of each period.
-Œ/'
)12 ##b
3 Display the TVM Solver. Enter
48 monthly payments, present
value of $9,000, payment amount
of L$250 (negation indicates
cash outflow), and future value
of $0. The Nvalue (48) was
derived from 4 (years) M
12 (months).
&48 ##9000
#a250 #0
b
4 Move the cursor to æ=(interest
rate) and then select SOLVE
from the TVM Solver menu. A
small square is displayed next to
the solution. The solution value
is stored to the TVM variable I.
$$$*
Computing Compound Interest
At what annual interest rate, compounded monthly, will $1,250 accumulate to
$2,000 in 7 years?
1 Display the payment format
editor. Set payments per year to
1 and compounding periods per
year to 12. Set payment due at
the end of each period.
-Œ/'
)1#12 #
b
2 Display the TVM Solver. Enter 7
annual payments, present value
of L$1,250 (negation indicates
cash outflow), payment amount
of $0, and future value of $2,000.
&7##a1250
#0#2000 b
3 Move the cursor to æ=(interest
rate) and then select SOLVE
from the TVM Solver menu. A
small square is displayed next to
the solution. The solution value
is stored to the TVM variable I.
$$$*
When you change
P/Y
,
C/Y
changes automatically.
As you enter a value at any
TVM Solver prompt, the
corresponding TVM variable
value is updated.
Because there are no
payments when you solve
compound interest problems,
you must set
PMT
to
0
and
set
P/Y
to
1
.
The decimal mode is fixed at
2
from the previous example.

Assembly Language Programming: Financial Functions
7
Using the Financial Functions
Entering Cash Inflows and Cash Outflows
When using the financial functions, you must enter cash inflows (cash received) as
positive numbers and cash outflows (cash paid) as negative numbers. The financial
functions follow this convention when computing and displaying answers.
FIN FUNC (Financial Functions) Menu -Œ/'
TVM FUNC VARS FORMT Uninst
tvmN tvmI tvmPV tvmP tvmFV 4npv irr bal Gprn Gint
4nom eff dbd pBegin pEnd
Calculating Time-Value-of-Money
The first five items on the FIN FUNC menu are the time-value-of-money (TVM)
functions. You can use them to analyze financial instruments, such as annuities,
loans, mortgages, leases, and savings, on the home screen or in a program.
tvmN [(
æ
,PV,PMT,FV,P/Y,C/Y)] Computes the number of payment periods
tvmI[(N,PV,PMT,FV,P/Y,C/Y)] Computes the annual interest rate
tvmPV [(N,
æ
,PMT,FV,P/Y,C/Y)] Computes the present value
tvmP [(N,
æ
,PV,FV,P/Y,C/Y)] Computes the amount of each payment
tvmFV [(N,
æ
,PV,PMT,P/Y,C/Y)] Computes the future value
Each TVM function takes zero to six arguments. Each argument must be a real
number or a TVM variable. The values that you specify as arguments for these
functions are not stored to the TVM variables.
If you enter less than six arguments, you must enter arguments in the order of the
syntax, up to the last argument you want to enter. The program substitutes a
previously stored TVM variable value for each subsequent unspecified argument.
If you enter any arguments with a TVM function, you must place the argument or
arguments in parentheses. The following examples show some ways to use the
TVM functions.
All arguments and
punctuation inside the
[ ]
brackets are optional.
To store a value to a TVM
variable, use the TVM Solver
or use
X
and any TVM
variable on the
FIN VARS
menu.

Assembly Language Programming: Financial Functions
8
Assume these values are stored to the TVM variables in the payment format editor and TVM Solver.
When you execute a TVM
function on the home screen
with no specified arguments,
the TVM function (
tvmPMT in
the example) uses stored TVM
variable values.
To change an argument without
changing the value stored to a
TVM variable, enter arguments
up to the argument you want to
change. In the example, the
interest rate is changed to
9.5 .
You can enter arguments
directly on the home screen.
Remember, neither the answer
nor the arguments are stored to
the TVM variables.
To store an answer to the
appropriate TVM variable, use
X
and the
FIN VARS
menu.
If you prefer, you can store
values to the TVM variables on
the home screen. When you execute a TVM
function (
tvmPV in the
example), it uses the newly
stored TVM variable values.
Calculating Cash Flows
The next FIN FUNC menu items are cash flow functions. Use them to analyze the
value of money over equal time periods. You can enter unequal cash flows. You
can enter cash inflows or outflows.
npv(interestRate,cashFlow0,
cashFlowList[,cashFlowFrequency])Returns the sum of the present values for the
cash inflows and outflows
irr(cashFlow0,cashFlowList
[,cashFlowFrequency])Returns the interest rate at which the net
present value of the cash flows is equal to 0
♦ interestRate is the rate by which to discount the cash flows (the cost of
money) over one period.
♦ cashFlow0 is the initial cash flow at time 0; it must be a real number.
♦ cashFlowList is a list of cash flow amounts after the initial cash flow cashFlow0.
♦ cashFlowFrequency is a list in which each element specifies the frequency of
occurrence for a grouped (consecutive) cash flow amount, which is the
corresponding element of cashFlowList. The default is 1; if you enter values,
they must be positive integers <10,000.

Assembly Language Programming: Financial Functions
9
The uneven cash flow below is expressed in lists. cashFlowFrequency indicates
that the first element in cashFlowList (2000) occurs twice (2), the second element
(L3000) occurs once (1), and the third element (4000) occurs twice (2).
cashFlow0 = 2000
cashFlowList = {2000,L3000,4000}
cashFlowFrequency = {2,1,2}
I% = 6
cashFlow0 = L2000
cashFlowList = {L2000,1000, L2500,0,5000,3000}
cashFlowFrequency = N/A
Calculating Amortization
Items eight, nine, and ten are the amortization functions. Use them to calculate
balance, sum of principal, and sum of interest for an amortization schedule.
bal(nPayment[,roundValue])Computes the balance for an amortization schedule;
nPayment (the number of the payment at which to
calculate a balance) must be a positive integer
<10,000
GPrn(paymentA,paymentB
[,roundValue])Computes the sum of the principal during a specified
period for an amortization schedule; paymentA (the
starting payment) and paymentB (the ending
payment in the range) must be positive integers
<10,000
GInt(paymentA,paymentB
[,roundValue])Computes the sum of the interest during a specified
period for an amortization schedule; paymentA (the
starting payment) and paymentB (the ending
payment in the range) must be positive integers
<10,000
roundValue
specifies the
internal precision used to
calculate the balance.
effectiveRate
,
nominalRate
,
and
compoundingPeriods
must be real numbers;
compoundingPeriods
must
be > 0.
bal(
,
GPrn(
, and
GInt(
use
stored values for
æ
,
PV
, and
PMT
. You must store values
to these variables before
computing the principal.
2000 2000 2000 4000 4000
L3000
CF0CF1CF2CF3CF4CF5
L2000 L2000
1000 5000 3000
L2500
CF0CF1CF2CF3CF4CF5
0
CF6

Assembly Language Programming: Financial Functions
10
Amortization Example: Calculating an Outstanding Loan Balance
You want to buy a home with a 30-year mortgage at 8 percent annual percentage
rate (APR). Monthly payments are $800. Calculate the outstanding loan balance
after each payment and display the results in a graph and in the table.
1 Display the mode screen and set
the fixed-decimal setting to 2, as
in dollars and cents. Also, set
Param graphing mode.
-m#
"""b
###""
b
2 Display the payment format
editor, and then set payments
and compounding periods per
year to 12, to be received at the
end of each period.
-Œ/'
)12 ##b
3 Display the TVM Solver, and
then enter the known TVM
variable values:
N=360 PMT=L800
I=8 FV=0
&360 #8##
a800 #0b
4 Move the cursor to the PV=
prompt and solve for the present
value of the loan. A small square
specifies the solution.
$$*
5 Display the parametric equation
editor. Turn off all stat plots.
6 Define xt1 as tand yt1 as bal(t).
6&(if a plot
is on, press $, "
to highlight it, and
b; then #)
&#-Œ
/''/
(-&E
7 Display the window variable
editor, and then enter these
window variable values as
shown.
6'0#360
#12 #0#360
#50 #0#
125000 #10000
8 Draw the graph and activate the
trace cursor. Explore the graph
of the outstanding balance over
time.
*
)
!"
9 Enter a value for tto view the
balance at a specific time.
24 b
A stat plot is turned on if it is
highlighted with a box.

Assembly Language Programming: Financial Functions
11
JDisplay the table setup editor,
and then enter these values:
TblStart=0 @Tbl=12
Indpnt: Auto
7'
0#12 #b
KDisplay the table of outstanding
balances, where xt1 represents
time and yt1 represents balance
at that point in time.
&
Calculating Interest Conversion
Use the interest conversion functions nom and eff to convert interest rates from an
annual effective rate to a nominal rate (nom), or from a nominal rate to an annual
effective rate (eff).
nom(effectiveRate,compoundingPeriods)Computes the nominal interest rate
eff(nominalRate,compoundingPeriods)Computes the effective interest rate
Finding Days Between Dates
Use the date function dbd to calculate the number of days between two dates
using the actual-day-count method. dateA and dateB can be numbers or lists of
numbers within the range of the dates on the standard calendar.
dbd(dateA,dateB)Calculates the number of days between dates; enter dateA and
dateB in either of two formats: MM.DDYY (for U.S.) or DDMM.YY
(for Europe)
Defining the Payment Method
pEnd and pBegin specify a transaction as an ordinary annuity or an annuity due.
Executing either instruction sets the payment method for subsequent financial
calculations. The current setting is displayed in the payment format editor
(page 4).
pBegin Specifies an annuity due, where payments occur at the beginning
of each payment period (Most leases are in this category.)
pEnd Specifies an ordinary annuity, where payments occur at the end
of each payment period (Most loans are in this category;
Pmt_End is the default.)
Dates must fall between the
years 1950 and 2049.
On the payment format
editor’s
PMT:END BEGIN
line,
select
END
to set ordinary
annuity or select
BEGIN
to
set annuity due.

Assembly Language Programming: Financial Functions
12
Menu Map for Financial Functions
MATH Menu (where FIN is automatically placed) -Œ
NUM PROB ANGLE HYP MISC 4INTER FIN
(MATH) FIN (Financial) Menu -Œ/'
TVM FUNC VARS FORMT Uninst
FIN TVM (Time-Value-of-Money) Solver Menu -Œ/'&
TVM FUNC VARS FORMT SOLVE
FIN FUNC (Financial Functions) Menu -Œ/''
TVM FUNC VARS FORMT Uninst
tvmN tvmI tvmPV tvmP tvmFV 4npv irr bal Gprn Gint
4nom eff dbd pBegin pEnd
FIN VARS (Financial Variables) Menu -Œ/'(
TVM FUNC VARS FORMT Uninst
çI PV PMT FV 4PY CY
FIN FORMT (Financial Format) Menu -Œ/')
TVM FUNC VARS FORMT