# prices_rate: Calculate Growth Rate From a Vector of Stock Prices or... In stocks: Fast Functions for Stock Market Analysis

## Description

The formula is simply: `overall.rate = prices[length(prices)] / prices[1] - 1`. If `units.rate` is specified, then it converts to x-unit growth rate.

## Usage

 `1` ```prices.rate(prices, units.rate = NULL, nas = FALSE) ```

## Arguments

 `prices` Numeric vector of stock prices or investment balances. `units.rate` Number of units for growth rate calculation. If unspecified, function returns total growth. To get annualized growth rate, set to 252 if `prices` has daily prices, 12 if `prices` has monthly prices, etc. `nas` If `TRUE`, function finds and removes any missing values (`NA`s) in `prices`. The default is `FALSE` to maximize speed for the usual case where there are no missing values.

## Value

Numeric value indicating the growth rate.

## Author(s)

Dane R. Van Domelen

## References

Acknowledgment: This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-0940903.

`gains.rate`
 ``` 1 2 3 4 5 6 7 8 9 10 11``` ```# Create vector of daily closing prices for a hypothetical stock prices <- c(100.4, 98.7, 101.3, 101.0, 100.9) # Overall growth is 0.50% prices.rate(prices) # Average daily growth is 0.12% prices.rate(prices, 1) # Corresponds to 36.6% annualized growth prices.rate(prices, 252) ```