# periodToDateMaxOverTime


The `periodToDateMaxOverTime` function calculates the maximum of a measure for a given time granularity (for instance, a quarter) up to a point in time.

## Syntax


```
periodToDateMaxOverTime(
	measure, 
	dateTime, 
	period)
```

## Arguments


 *measure*   
An aggregated measure that you want to do the calculation

 *dateTime*   
The date dimension over which you're computing PeriodOverTime calculations.

 *period*   
(Optional) The time period across which you're computing the computation. Granularity of `YEAR` means `YearToDate` computation, `Quarter` means `QuarterToDate`, and so on. Valid granularities include `YEAR`, `QUARTER`, `MONTH`, `WEEK`, `DAY`, `HOUR`, `MINUTE`, and `SECONDS`.  
The default value is the visual's date dimension granularity.

## Example


The following example calculates the maximum fare amount month over month.

```
periodToDatemaxOverTime(max({fare_amount}), pickupDatetime, MONTH)
```

![\[This is an image of the results of the example calculation with illustrations.\]](http://docs.aws.amazon.com/quick/latest/userguide/images/PTDMaxOverTimeResults.png)