the Dil-zen exchange ratio is set completely by players. The devs can only control the maximum and minimum possible values. The current price is constantly changing and is determined by the individual players using the dil exchange. If you really want to raise the price of the exchange, buy up as much cheap zen as you can.
Gotcha - appreciate the input. I don't use it very often, so I didn't know the Exchange worked like that. Have thought all along that it was a PWE/Cryptic-run device.
It actually is very cool that the players have some sort of control over at least one currency. I agree with the play vs. Zen thing, but thought I might spend my stipend on a bit of the purple stuff - sure as hell not going to use it for the overpriced crap in the Zen store...
(...actually active since November 2010, which may one day be important to archaeologists, but not to anyone else...)
As it's mostly market driven the season 6 changes have contributed heavily to the price change. There are a lot of projects requiring dilithium and many new items that require dilithium so dilithium demand is up a lot. Higher tier starbases have items that cost fleet credits and dilithium.
So for those that need dilithium going $$$ -> zen -> dilithium is getting more expensive.
Of course those that want to trade dil -> zen this is a good situation.