Bitcoin Traffic Collapse

From late April until late September, Bitcoin network ran at a saturated rate and queued up transactions. For five months, there was never enough bandwidth to process the backlog so transactions piled up or expired. In late September, Bitcoin's traffic suddenly dropped by 41%, which freed up bandwidth to execute the older entries, which led to the HUGE transaction time of 430 hours.

A 41% drop in transactions usually comes with a similar price drop. So far, it hasn't happened and I'm curious about the cause of such a drastic change.

Update: Bitcoin traffic now down 47%.