{"identifier":51607,"topic":"Functions","name":"annuity","text":"<code>annuity(<i>number1<\/i>, <i>number2<\/i>)<\/code> <br><br>\n\n where<code> <i>number1<\/i> <\/code>represents the  <b>interest rate<\/b> (expressed as a decimal)  and<code> <i>number2<\/i> <\/code>represents the number of <b>periods<\/b> over which you receive annuity payments. <br><br>\n\n Value returned: the total cost of an annuity now that will pay you one unit per period over the specified number of periods, or a number equal to <code>(1 - (1 + rate) ^ -periods) \/ rate<\/code> <br>\n<br>\nAn interest rate involves a certain percentage (expressed as a decimal) per some unit of time\u2014usually per year. You must use the same unit of time to measure the number of periods. <br><br>\n\n For example, if you have a yearly percentage rate but your annuity pays you monthly, use <code>rate \/ 12,<\/code> and be sure to express the number of periods as months (2 years = 24 months). <br>\n","related":{"89523":"Arithmetic operators","54407":"compound","78162":"numberFormat"},"examples":"","demo":"","debug":{"9":["annuity(number1, num"],"10":["An interest rate inv"]}}