Regular returns (log-differenced prices) have statistical distributions that are bell-shaped and unimodal (one mode/peak) despite being non-normal and fat-tailed.
Cumulative returns, on the other hand, computed from regular returns as $[\prod (1+r)] -1$, are bi-modal (with two modes/peaks). Is there a reason for cumulative return distributions having this shape?
And in spite of cumulative returns being non-stationary unlike regular returns, are they used in any well-known financial models at all?