The best place to find this on the customers-level would be in your Customers - Last Order Analysis page under the RFM section (about half way down the page). There is a chart titled "Customers by Orders Count & Acquisition Age" that shows count of
customers broken down by
acquisition age. You can also use the filters at the top of the page to scope the page to certain segments of customers (e.g. repeaters only, subscribers only, customers who ordered a sample or starter kit on their first order etc.)
You could also find this on the orders-level in the Orders Deep dive page.