# Find annual | monthly cumulative (product) of returns

Category:Blog

## The problem

Let’s say that we have daily stock returns. We want to convert those returns to cumulative returns for a weekly, monthly or yearly frequency.

Where cumulative returns = (1+Ri1) * (1+Ri2) * (1+R3) * … (1+R4) – 1

## Solution

First create the weekly, monthly or year identifier, and then use asrol program.

Let us use this data set [Click here to download], also shown below and find returns for different frequencies.

```input id str20 D returns
1 30jun1993 .7437958
1 02jul1993 .0674011
1 06jul1993 .2668857
1 14jul1993 .0454151
1 19jul1993 .1340756
1 29jul1993 .8053644
1 13aug1993 .5861199
1 24sep1993 .3200437
1 19oct1993 .0098762
1 19oct1993 .005197
end
g date = date(D, "DMY")
drop D```

### Find weekly cumulative returns

Let us first install asrol from ssc

`ssc install asrol`

Now create weekly date

`gen week = wofd(date)`

Now find the returns using asrol

`bys id week :  asrol returns, stat(product) add(1)`

Note : add(1) adds 1 with each returns before multiplication and then subtracts 1 at the end.

### Find monthly cumulative returns

```gen month = mofd(date)
bys id month:  asrol returns, stat(product) add(1)```

### Find yearly cumulative returns

``` gen year= year(date)
bys id year:  asrol returns, stat(product) add(1)```