GPU Prices Drop ~25% in March as Supply Normalizes
wccftech.com
wccftech.com
The new ASICs for Ethereum mining can't be solely responsible for this percent of the market.
(Note that NVIDIA's stock price is up over 1700% over the past 10 years. And that Bitcoin mining on CPUs and GPUs hasn't been profitable for quite awhile. In 2007, I don't think we knew that hashing could be done on GPUs; though there were SSL accelerator cards that were mighty expensive)