HP 12C Financial calculator User Manual
Page 192
192 Appendix D: Formulas Used
File name: hp 12c_user's guide_English_HDPMBF12E44
Page: 192 of 209
Printered Date: 2005/7/29
Dimension: 14.8 cm x 21 cm
(
)
( )
⎥
⎥
⎦
⎤
⎢
⎢
⎣
⎡
−
⋅
⎥
⎥
⎦
⎤
⎢
⎢
⎣
⎡
−
⎥⎦
⎤
⎢⎣
⎡
⋅
−
=
∑
∑
∑
∑
∑
∑
∑
n
y
y
n
x
x
n
y
x
xy
r
2
2
2
2
Standard Deviation
(
)
)
1
(
2
2
−
−
=
∑
∑
n
n
x
x
n
s
x
( )
)
1
(
2
2
−
−
=
∑
∑
n
n
y
y
n
s
y
Factorial
0! = 1
For n > 1 where n is an integer:
∏
=
=
n
i
i
n
1
!
The Rent or Buy Decision
Market Value = PRICE(1 + I)
n
where:
I
= appreciation per year (as decimal)
n
= number of years
Net Cash Proceeds on Resale = Market Value – Mortgage Balance – Commission
The interest rate is obtained by solving the financial (compound interest) equation
for i using:
n
= number of years house is owned
PV
= down payment + closing costs
PMT
= mortgage payment + taxes + maintenance
– rent – (% tax)
(interest + taxes)
FV
= net cash proceeds on resale
Annual interest rate = 12 × i