How to calculate returns from a vector of prices?

Question

I have to calculate the return of a vector that gives a historical price series of a stock. The vector is of a form:

a <- c(10.25, 11.26, 14, 13.56) 
         


        

Answer 1

You may find the functions in quantmod relevant for your work:

> require(quantmod)
> Delt(a)
     Delt.1.arithmetic
[1,]                NA
[2,]        0.09853659
[3,]        0.24333925
[4,]       -0.03142857