I can show you charts that
I can show you charts that show the same for automotive in general. The same trends held true of Mazda's rotary engine back in the day. Same with the iPhone 6. The fact that the trend changed this year could be indicative of a lot of things. Most likely it's indicative of the plug-in market having saturated as-is. Nevermind that the chart is counting from zero. Versus the automotive market as a whole, which John pointed out, plug-ins are not growing in terms of percentage of total market. They haven't been for some time. They barely keep up with market growth. THAT, friend, is an actual trend that matters. Only hybrids with no plug can claim to be growing in rates of purchase commensurate with market growth for the automotive sector. Both of these facts would indicate that the plug-in market has reached a saturation point.