I see it now. I believe the blog post author is mistaken though: the majority of the examples he provided were first loans.
I'll go back and look at the 20 loans with your tip in mind, and recalculate APRs separately for both first-time borrowers and repeat borrowers, and update the post.
I see what you mean. This is confusing because our website is programmed to display the registration fee only for applicants who have not yet had a loan disbursed. Once a loan is disbursed, the fee is paid and is no longer displayed in the loan profile page as part of the amount due to be paid by the borrower.
The second and subsequent loans contain a link "View previous loans" under the "On-Time Repayments" record in the right panel. All the loans that do not have that link are first loans.