Misleading weighted average portfolio age calculation by lendingclub

I have a Lendingclub account, while I like the transparency Lendingclub provides than Prosper (horrible UI), sometimes the calculation can be misleading.
I looked at my portfolio weighted average age as a measure of how soon I can get my investment back if I stops investing.  For example, given most of my loans' terms are 36 months and a weighted average portfolio age of 20; It is reasonable to assume that I can get my investment back in 16 (36-20) months or less.  Except it is WRONG!  I was doing my own calculations recently and found out that the portfolio weighted average age calculation includes terminated loans!  So, if a loan has already been charged off 8 months ago, it will still "age" and contribute to portfolio age!  To truly estimate my expected number of months to get my investment, these terminated loans must be excluded in weighted age calculation.  After removing them and my true weighted average age is 10, which means I really have to wait 26 months instead of 16!
I suspect this could mislead people to understand comparable returns against other portfolios because younger portfolio have larger return than older ones.  By making portfolio looks older, people are more likely to accept lower return since other similar "age" portfolios' returns are not that high either.