Appendix D: オプション関数ライブラリ
これは金利計算や月賦払いなど、多岐にわたる一般的な財務計算をサポートするオプションライブラリである。
- apr(n1, n2, n2)
- n1を貸付の基礎金額、n2を月賦払い、n3を支払月数とした場合の、貸付の年次利率を返す。
たとえば、"
apr(35000, 269.50, 30 times
12)"は$35,000の貸付が毎月$269.50の30年払いとして支払われた場合の利率0.085(あるいは8.5%)を返す。
- cterm(n1, n2, n2)
- n1が期間毎の利率、n2が投資の将来値、n3が初期投資の総計して、利率を将来値まで成長させる、固定金額かつ複雑計算に基づく投資回収に必要な期間数を返す。
たとえば、"
cterm(.02, 200, 100)" は$100が2%で$200まで成長するために必要な期間35を返す。
- fv(n1, n2, n3)
- n1が各支払金額、n2が期間毎の料率、n3が期間数である場合の、固定利率かつ固定支払い期間の将来値を返す。
たとえば、"
fv(100,
.075 over 12, 10 times 12)"は毎月$100の10年間の年率7.5%の支払いの結果となる総金額17793.03を返す。
- ipmt(n1, n2, n2, n3, n4,
n5)
- n1を貸付の基礎金額、n2を年次利率、n3を月賦、n4を計算の最初の月、n5を計算される月数とした場合の、所定の期間の貸付で支払われる利息の総計を返す。
たとえば、"
ipmt(30000, .085,
295.50, 7, 3)"は利率8.5%の$30,000.00の貸付が毎月$295.50ずつ、7月から3ヶ月支払った場合の利息の総計624.88を返す。
- npv(n1, n2 [, ...])
- Returns the the net present value of an investment based on a discount rate,
and a series of periodic future cash flows, where n1 is the discount rate
over one period, n2 ... are cash flow values which must be equally spaced
in time and occur at the end of each period. For example "
npv(0.15,
100000, 120000, 130000, 140000, 50000)" returns 368075.16 as the net
present value of an investment projected to generate $100,000, $120,000, $130,000,
$140,000 and $50,000 over each of the next five years and the rate is 15%
per annum.
- pmt(n1, n2, n3)
- Returns the payment for a loan based on constant payments and a constant
interest rate, where n1 is the principal amount of the loan, n2 is the interest
rate per period, and n3 is the number of monthly payments. For example, "
pmt(30000.00,
.085 over 12, 12 times 12)" returns 333.01 as the monthly payment for
a loan of a $30,000, borrowed at a yearly interest rate of 8.5%, repayable
over 12 years (144 months).
- ppmt(n1, n2, n2, n3, n4,
n5)
- Returns the amount of principal paid on a loan over a period of time, where
n1 is the principal amount of the loan, n2 is annual interest rate, n3 is
the monthly payment, n4 is is the first month of the computation, and n5 is
the number of months to be computed. For example "
ppmt(30000, .085,
295.50, 7, 3)" returns 261.62 as the amount of principal paid starting
in July (month 7) for 3 months on a loan of $30,000 at an annual interest
rate of 8.5%, being repaid at $295.50 per month. The annual interest rate
is used in the function because of the need to calculate a range within the
entire year.
- pv(n1, n2, n3)
- Returns the present value of an investment of periodic constant payments
at a constant interest rate, where n1 is the amount of each equal payment,
n2 is the interest rate per period, and n3 is the total number of periods.
For example "
pv(1000, .08 over 12, 5 times 12)" returns 49318.43
as the present value of $1000.00 invested at 8% for 5 years.
- rate(n1, n2, n3)
- Returns the compound interest rate per period required for an investment
to grow from present to future value in a given period, where n1 is the future
value, n2 is the present value and n3 is is the total number of periods. For
example "
rate(110, 100, 1)" returns 0.10 as what the rate of
interest must be for and investment of $100 to grow to $110 if invested for
1 term.
- term(n1, n2, n3)
- Returns the number of periods needed to reach a given future value from
periodic constant payments into an interest bearing account, where n1 is the
payment amount made at the end of each period, n2 is the interest rate per
period, and n3 is the future value. For example "
term(475, .05, 1500)"
returns 3 as the number of months for an investment of $475, deposited at
the end of each period into an account bearing 5% compound interest, to grow
to $1500.00.