Unfortunately, I haven't been able to get the powerdown data ever since the big performance issues last year. This SteemDB.io page hasn't updated since September 4, and that's what I was using to build the powerdown graph. I'd have to rebuild the data by going through the operations block by block. A big part of the reason why I stopped publishing those posts was that several different steemdb.io pages that I needed had all stopped updating. I do keep an eye on pending powerdowns, but I haven't been recording them. (it's presently back down in the 300-400K per week range, after spending some weeks or months up near 900k or a million.)

I guess it wouldn't be too difficult to slap together a script to update the last 7-8 months. Maybe I'll spend some time on that in the next week or three...