Find net present value, calculate loan repayment amounts, calculate required payments for desired retirement amount. Support for irregular and regular cash flows and you can even estimate net present value of a constant perpetuity (by using large number of cash flows). Included calculator for Effective Annual Rate as well as Periodic Rate.

******* INSTRUCTIONS *******

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Present value of annuity with payments at the end of the period
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1. Set number of periods in annuity. (NPer)
2. Enter the dollar amount of the annuity payments into CF_t and tap the [All] button.
3. Since we don't want the first cash flow since it is at the beginning of the period enter 0 into CF_t and tap the [Current] button.
4. Now set the periodic interest rate and tap [Compute NPV]

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Future value of investment (single cash flow)
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1. Set NPer to number of periods amount is invested
2. Enter a cash flow amount into CF_t as the amount to invest then press [Current]
3. Set the focus to the last period and tap [Compute NPV]

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Find what the required equal payments are to achieve desired savings X by year N
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1. Set NPer to N
2. Set focus to N
3. Enter X at time N in CF_t and then tap [Current], in other words enter desired amount at the end of the last period.
4. Move the focus to where the first regular equal payment is to be made. (usually either t = 1 or t = 0)
5. Check the Annuity Due box if you would like to make the last payment at the beginning of the last period, or leave it unchecked if you would like the last payment at the end of the last period.

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General instructions
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1. Always place the focus on where you want the first payment to be made when using the payment calculator component of this app.
2. The [periodic rate] button simply divides the nominal rate by the number of compounding periods in a year and puts the result as the periodic interest rate.
3. The [Use EAR] button calculates the effective interest with periodicity of a year given the nominal rate and number of compounding periods per year, again the result is set as the periodic interest rate.

This app is not a substitute for studying and accurate answers are not guaranteed, there is a certain degree of rounding error especially for larger numbers, whether this affects you depends on how you use it.

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