339
Investment Appraisal
19 - 4
19-5
Amortization of a Loan
This calculator can be used to calculate the principal and interest portion of a
monthly installment, the remaining principal, and amount of principal and interest
repaid up to any point.
b
a
d
e
c
1 2
m
n
a
: Interest portion of installment PM1 (
INT
)
b
: Principal portion of installment PM1 (
PRN
)
c
: Balance of principal after installment PM2 (
BAL
)
d
: Total principal from installment PM1 to payment of installment PM2 (
%
PRN
)
e
: Total interest from installment PM1 to payment of installment PM2 (
%
INT
)
*
a
+
b
= one repayment (
PMT
)
a
:
INT
PM1
=
I
BAL
PM1–1
!
i
I
!
(
PMT
sign
)
b
:
PRN
PM1
=
PMT
+
BAL
PM1–1
!
i
c
:
BAL
PM2
=
BAL
PM2–1
+
PRN
PM2
d
:
%
PRN
=
PRN
PM1
+
PRN
PM1+1
+ … +
PRN
PM2
e
:
%
INT
=
INT
PM1
+
INT
PM1+1
+ … +
INT
PM2
PM2
PM1
PM2
PM1
BAL
0
=
PV
(
INT
1
= 0 and
PRN
1
=
PMT
at beginning of installment term)
u
u
u
u
u
Converting between the nominal interest rate and effective interest
rate
The nominal interest rate (
I
% value input by user) is converted to an effective
interest rate (
I
%') for installment loans where the number of installments per year
is different from the number of compound interest calculation periods.
I%' =
I%
(1 +
)
–1
[
C
/
Y
]
[
P
/
Y
]
100
!
[
C
/
Y
]
{ }
!
100
(Number of payments)
Amount of single payment
Summary of Contents for CFX-9970G
Page 22: ... CFX 9970G ...
Page 452: ...435 1 2 3 4 5 Program for Circle and Tangents No 4 Step Key Operation Display ...
Page 453: ...436 Program for Circle and Tangents No 4 Step Key Operation Display 6 7 8 9 10 ...
Page 454: ...437 11 12 13 14 15 Program for Circle and Tangents No 4 Step Key Operation Display ...
Page 455: ...438 16 17 18 Program for Circle and Tangents No 4 Step Key Operation Display ...
Page 458: ...441 1 2 3 4 5 Program for Rotating a Figure No 5 Step Key Operation Display ...