Ask and you shall receive! I'm still looking for a good means to get historical data (there are many APIs out there but I'm no computer whiz so no idea how to leverage), but below is the gross volume (calculated on a per unit), and then below that I normalize it based on price (because obviously we expect more volume for something worth $.01 vs $10000). Bitcoin is still the king!
You can get decent data from bitfinex. (just one place I've found handy) Also this is pretty cool (if not slightly unrelated...): http://github.com/butor/blackbird
Thanks!