Thank you OrientExpress!
This also matches the price trends on the CarGurus website here. Price change for the 2015 LEAF, Year-over-Year as reported today: +22%!https://www.cargurus.com/Cars/price-trends/Nissan-Leaf-d2077
I believe those are average listed prices on CarGurus, not what buyers actually pay, but it matches the trend that OrientExpress sees at auction.
There is a cool chart there too. You can change model years in the chart by ticking boxes lower on the page, and if you adjust the dates in the top left to show the past four years or so and click 'Update Chart' you'll see the price curves go up.
Actually, to me it seems that LEAFs are reverting back to a pretty normal depreciation curve, but for some reason they were very cheap for a while around Spring 2017.
I got a great deal on a 2014 about a year ago and I get giddy every time I look up the price trends.