HP 12C, Руководство пользователя

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Appendix E: Formulas Used 257
File name: HP 12c Pt Converted_user's guide_English_HDP0F123E02_080207 Page: 257 of 281
Printed Date: { 2007/8/2Dimension: 14.8 cm x 21 cm
Discounted Cash Flow Analysis
Net Present Value
NPV = net present value of a discounted cash flow.
CF
j
= cash flow at period
j .
n
n
i
CF
i
CF
i
CF
CF NPV
) 1 (
...
) 1 (
) 1 (
2
2
1
1
0
+
+ +
+
+
+
+ =
Internal Rate of Return
n = number of cash flows
CF
j
= cash flow at period j .
IRR = Internal Rate of Return
0
1
) 1 (
) 1 ( 1
0 CF IRR
IRR
IRR
CF
j q
j
nq
k
j
n
j
+
⎥
⎦
⎤
⎢
⎣
⎡
+ ⋅
⎥
⎥
⎦
⎤
⎢
⎢
⎣
⎡
+ −
⋅ =
∑
−
=
−
<
∑
Calendar
Actual Day Basis
Δ
DYS = f( DT
2
) – f( DT
1
)
where
f( DT ) = 365 ( yyyy ) + 31 ( mm – 1) + dd + INTG ( z /4) – x
and
for mm
≤
2
x = 0
z = ( yyyy ) – 1
for mm > 2
x = INTG (0.4 mm + 2.3)
z = ( yyyy )
INTG = Integer portion.
Note: Additional tests are performed in order to ensure that the century (but
not millennium) years are not considered leap years.
30/360 Day Basis
DAYS = f( DT
2
) – f( DT
1
)
f( DT ) = 360 ( yyyy ) + 30 mm + z
for f( DT
1
)
if dd
1
= 31 then z = 30
if dd
1
≠
31 then z = dd
1
for f( DT
2
)
if dd
2
= 31 and dd
1
= 30 or 31 then z = 30
if dd
2
= 31 and dd
1
< 30 then z = dd
2
if dd
2
< 31 then z = dd
2