New passports, including renewals, have a microchip. That partly increases the price. Government has also been moving towards a "user fee" model, which I think (but cannot swear) has also had an impact here. For a time, government attempted to keep fees low so that, say, one didn't have to be rich just to go to Canada (now that one needs a passport to get there) and subsidized the State Department through income and corporate taxes. Over a number of years now, income taxes have actually been cut (see the Wikipedia graph: it seems to match data from both left and right that I've also been able to find online, and it's the easiest to read). Corporate taxes have also been cut. Fees for various services are having to carry a larger burden as top income tax rates have been reduced and estate tax has been decreased—and is currently suspended, so that this year no estate tax is being collected in this country. The estate tax could be reinstated.

I think the trend will only continue: we will pay more for specific things from government as the burden shifts further from taxes to user fees. Personally, I don't think this is a good thing.