# How to add/sum up series?

If you want to sum values across few series, there are two main ways to achieve this:

### 1. Formula language

You can sum multiple series by typing a simple expression with the '+' sign.

It will add up only common part for all series.

### 2. Cross Section analysis

Use the Cross section analysis to calculate a sum across series. This is a good option if you want to summarize a lot of series since you can easily include several series at once.

Cross section Sum option works the same as adding series using '+' sign. However, it is worth noting that the result will differ if you untick 'Include only observation where there are values for all series' option. Then Cross section will add values at all available points in time.

### Sum(series) formula

In case you want to sum values of one series Sum(series) formula will be helpful. It only sums the values of one series, the output would be a repeated value for all observations, because it returns the sum of all the numbers in the series.