Innovation Slowdown? Not According to Patent Data

I'm reading Tyler Cowen's provocative book "The Great Stagnation" and blogging at 30,000 feet in the air on a Delta flight to Minneapolis (pretty amazing to be able to do that!).  Here's a quote from p. 20 in the first chapter of the book where Tyler discusses the supposed slowdown in innovation, supported by this factoid:

"The United States produced more patents in 1966 (54,600) than in 1993 (53,200)."