These are ASIC included stats. Unfortunately, the non-asic stats I could find do not go back to the pre-gridcoin era. I think this is something to be considered when viewing these stats, particularly in chart 1, but I doubt that ASICs alone can be responsible for the trends we see in these charts.
Looking at the dates you bring up, I think a correlation connection to Gridcoin is more accurate than a connection to ASICs, but only better stats can say for sure.
I know you do stats so much better than I do, so if you've got things to add, please do! = )
The Bitcoin Utopia project handed out an enormous amount of credit.
Thanks @jimbo, I think this is a very important driver. The credit growth of Bitcoin Utopia matches the steep increase of overall credit nicely.
Good point!