Is anyone still getting delta updates?

Delta updates have been working great since Google first enabled them, but a couple of months ago I noticed that whenever I was updating apps, I was downloading the entire app again. I kinda forgot about this issue until yesterday when I was updating some apps. Before, the progress bar for an update would stop before getting to 100%, and then installing the portion that was downloaded. Now, it's always filling up to 100%, which makes me think there's a problem.

I don't think this is a change to the new Play Store either, as it was doing this in the old version of the store as well. It doesn't matter if it's a big game or a small app, delta updates just seem to not work for me anymore. Did Google disable them or something, or is it just me?