I think the other factor to keep in mind is that Bitcoin is still wildly inflationary, much more so than USD.

Each day 3200+ coins are minted, and at $500 price tag, requires $1.6M new money to enter the Bitcoin economy, every single day, just to maintain the $500 price tag.

When less than $1.6M enters, price -> fall. Until a new equilibrium is reached.

On the other hand, if more than $1.6M enters each day, then price will rise.