# How to Calculate a Cumulative Sum in SAS (With Example)

You can use the following basic syntax to calculate a cumulative sum in SAS:

```data new_data;
set original_data;
retain cum_sum;
cum_sum+sales;
run;
```

This particular syntax creates a new dataset called new_data that contains a new column called cum_sum that contains the cumulative values of the column called sales.

The following example shows how to use this syntax in practice.

## Example: Calculate a Cumulative Sum in SAS

Suppose we have the following dataset in SAS that shows the number of sales made by some store during 10 consecutive days:

```/*create dataset*/
data original_data;
input day sales;
datalines;
1 7
2 12
3 14
4 12
5 16
6 18
7 11
8 10
9 14
10 17
;
run;

/*view dataset*/
proc print data=original_data;``` The following code shows how to create a new dataset that calculates the cumulative sum of values in the sales column:

```/*calculate cumulative sum of sales*/
data new_data;
set original_data;
retain cum_sum;
cum_sum+sales;
run;

/*view results*/
proc print data=new_data;
``` The new column called cum_sum contains the cumulative sum of values in the sales column.

For example:

• Cumulative Sum on Day 1: 7
• Cumulative Sum on Day 2: 7 + 12 = 19
• Cumulative Sum on Day 3: 7 + 12 + 14 = 33

And so on.