# Built-in Functions → toDate with ago

toDate() with ago() is a combined time series analytic function that first calculates the ago() function value, which is the aggregated value of a measure from a specified start date (e.g. 10/01/2021) back to a specified period of time, such as a month, quarter, or year ago (e.g. a quarter ago, 07/01/2021), and then calculates the toDate function value, which is the aggregated value from the previously specified start date (e.g. 10/01/2021) to a specified period of time, such as a month, quarter, or year later (e.g. a month later, 11/01/2021). The output of the toDate() with ago() function is the summation of the aggregated values (e.g. from 07/01/2021 till 11/01/2021).

Note

You can add the toDate() with ago() formula column to the Measure tray only.

## Signature

```ago( toDate( date exp, string datePart), int rollBack, string datePart )
```

The following table illustrates the combined toDate() with ago() function parameters:

ParameterDescription
date expA column of type Date or a formula that outputs date
int rollBackThe integer value to roll back from `datePart`. A negative value adds up to `datePart`.

For example, if the value of `string datePart` is `"MONTH"`, then the value of `int rollBack` can be as follows:
•   `1` representing the last month
•   `-1` representing the next month
string datePartThe `string datePart` is a time dimension. The options are:
•   `"MONTH"`
•   `"QUARTER"`
•   `"YEAR"

## Returns

`double`, `date`, or `timestamp`

## Example

Consider a scenario where you want to calculate the accumulated sales revenue of a year and the year before. In this case, you must use an aggregation function, toDate () function, and an ago() function to perform your calculation.

```sum(   SALES.SALES.AMOUNT_SOLD,   ago(       toDate(           SALES.SALES.TIME_ID,           "Year"       ),       1,       "Year"   ))
```

Use the following steps for detailed instructions on how to use the todate() with ago() combined time series function to tackle the above example in an insight:

Note

In the Cluster Management Console (CMC), you can create a tenant that includes Sample Data. The Sample Data includes the SALES schema.

• In the Navigation bar, select the Content tab, and then select + New → Add Dashboard.
• In the Add Dashboard dialog, for Name, enter Product Dashboard, and then select Add.
• In the Action bar, select + (add icon), or select + Add Insight.
• In the Insight panel, select Listing Table or V.
• In Tables, select Aggregated Table.
• In the Data panel, select Manage Dataset.
• In the Manage Data Sets panel, in Tables, select SALES. Close the panel.
• From the Data panel, drag and drop the following columns from the SALES table to the respective tray:
• Sales Date to the Grouping Dimension tray
• In the Properties panel, for Date Part, select Year.
• Revenue to the Measure tray
• In the Properties panel, for Number Format, select Dollar Rounded.
• From the Data panel, drag and drop Add Formula to the Measure tray.
• The Formula Builder automatically opens:
• In Search Functions, select the down arrow, and then select Aggregation Functions.
• Double-click the second sum function, `sum(double[] exp)`, to add the formula to the editor.
• In the Formula Editor,
• Replace `double[] exp, ...` with Revenue from the Data panel, and then add a comma.
• In Search Functions, select the down arrow, and then select Analytic Functions.
• Double-click the ago function, `ago(date exp, int rollBack, string datePart)`.
In the Formula Editor,
• Replace `date exp` with toDate, `toDate(date exp, string datePart`, from the Functions panel
• Edit the toDate formula
• Replace `date exp` with Sales Date from the Data panel
• Replace `string datePart` with `"Year"`
• Replace `int rollBack` with `1`
• Replace `string datePart` with `"Year"`
```sum(SALES.SALES.AMOUNT_SOLD, ago(toDate(SALES.SALES.TIME_ID,"Year"),1, "Year")
```
• Select Validate & Save.
• In the New Formula Properties panel,
• For Column Label, enter Yago with YTD.
• For Number Format, select Dollar Rounded.
• Name the insight Revenue: Year ago with year toDate.
• In the Action bar, select Save.