Yes.
Coming from a potato-producing area and farm, I'd have to say that with plant breeding and genetics as they are, and with improved conservation and everything else that we do on our farms—improved agronomy, site specific, everything—generally we are seeing yields not decline.
On my farm, we do not irrigate. I'm one of six who owns my farm; I'm not the only one. We don't wish to irrigate. We don't grow for a processor. We grow for table. Our yields are either steady or increasing year over year. A lot of it is Mother Nature. Some people aren't looking for increased yield; they're looking for a different product.
We have the Little Potato Company growing small potatoes. That means they do it in a shorter time frame and they take off a lower yield. It's in the farmers' nature to want the most per acre, but the bottom line is different than that.