How do I measure how much revenue my abandoned cart emails brought back?

Several tabs in Abandoned Carts answer this:

• Overview: the Recovered value card.
• Conversions: each recovered order with its Recovered value, Won by (which email in the sequence brought it back, such as Email 2) and Ordered at. You can export it as CSV.
• Reports: per day Emails sent, Links recovered, Carts converted and Revenue recovered for a date range, with a chart and CSV export.
• Analytics: the funnel from Abandoned to Emailed, Recovered and Converted, plus Revenue recovered.

Won by tells you which reminder is worth keeping.