You'll have seen from previous threads with explanations that we calculate an IRR every month, for an annual cohort of loans written up to 3 months previously.
By way of an update and including the most recent monthly loan cohorts performance, the IRR as at 1st October 2019 is 13.6% (all loans from 1 July 2018 to 30 June 2019). The period is always chosen so that all loans have reached maturity and therefore defaults have peaked, in theory returns can only increase from here as a result of recoveries. It's jumped up to 13.6% from the last reported IRR of 10.7% as loans written since the summer of 2018 have performed significantly better than before, largely due to optimised credit policies and mix of customer sources.
That said, 13.6% is in my opinion too high and I expect it to reduce in the future. We don't state a target annualised return on the web-site, but probably something closer to <10% is where I'm thinking (I posted my thoughts on target returns on the Lending Works thread on the subject).
As per recently introduced FCA requirements, we will be enhancing our IRR reporting on the web-site before Christmas.