Here are links to the Bulk Activity Extract API and regular non-bulk activities API (use bulk over the regular for larger data extracts). Use the get activity types endpoint to get the IDs of the activity types you wish to export (you'd need to reference activity types you wish to extract in bulk/regular APIs using their respective ID).
Theoretically, you could also create Email Performance reports in Marketo, extract data in CSV, and run queries against it to analyze the deliverability based on the send date, but a solution via API is more scalable and it doesn't involve logging into Marketo, refreshing reports, and downloading the data.