Some data sources don't give back data with timestamps. For example the Twitter API can't tell you how many followers you had a week ago. It can only tell you how many followers you have today.
Luckily, Grow takes snapshots of metrics so you can see the metric history. Grow will save up to 30 "snapshots" for each metric.
View a Metric's Snapshot History
Let’s say you want to see how a metric looked in the past (yesterday, last week, last month).
Go to one of your metrics and expand it.
In the upper left-hand corner of your metric, you'll see three buttons. The click with the counterclockwise arrow shows you the snapshot history of your metric.
This will show all of the snapshots for the last month or so. Clicking on one will show you what the metric was at that time.
Change the Snapshot Interval
To change how often Grow takes a snapshot of the metric, go to Edit metric, and while in the 'Chart' side of the builder, click on Snapshot Interval in the Settings section in the bottom left.
In the window that pulls up, you can set how often Grow will take a snapshot of your metric. You can set the start time, the time zone, and the frequency (daily, weekly, or monthly). When you have set your snapshot interval, simply click off the box, and your changes will be applied to the metric upon saving the metric itself.
It is important to note that the start time does not mean the snapshot will be taken at that exact time, it just means that is the time in which the metric gets put into a queue and waits in line for the snapshot to be taken. After that, it will follow the 'Period' you have set for how often it continues to send out for a new snapshot. If you are looking to see your metrics at a specific time, we recommend using Grow's automated PDF Reports feature.