Update March 12: OASPA has added a downloadable spreadsheet with the data - thanks, OASPA! Note that the spreadsheet does not include a license - perhaps it is as obvious to OASPA as it is to me that data mining of the spreadsheet requires no such license?
The OASPA blog today features a chart illustrating Growth in the Use of the CC-BY License
Ironically this post demonstrates that CC-BY is not sufficient for one of its most touted goals, facilitating data and text mining. A picture-based chart is placed on a CC-BY licensed blog, but the data is not posted and there is no explanation provided of the method for collecting the data, which limits both our ability to interpret the data and (were the data available) our ability to mine or re-use the data.
If the data had been posted in downloadable format, then anyone could have mined it. There would have been no need to check the license of the blog.
One reason why some of us might like to download the data is to compare with other metrics. For example, I suspect that the growth curve of the use of the CC-BY license reflects to a large extent the overall Dramatic Growth of Open Access. In contrast with OASPA, my Dramatic Growth series features a full downloadable dataset. Feel free to data mine away!