The Wall Street Journal reported numbers this week that released by the Cleantech Group indicating $1.7 billion in VC investments globally in the fourth quarter of 2008. The story lead with the observation that this was the “steepest quarterly drop in two years” and “the smallest amount in six quarters.” But how does $1.7 billion look in the context of VC activity generally?

According to Cleantech again, US-based clean tech VC investments in the third quarter amounted to $1.7 billion–equal to the global total in Q4. It’s also more VC investment that flowed to any single industry sector in the third quarter, according to PriceWaterhouseCoopers and the National Venture Capital Association.

If you look at the NVCA/PWC chart you may well wonder how to compare their industry classifications with Cleantech’s. Clean tech as a category would seem to span 4 or more of the standard categories enumerated there.

I’ve got a note into Cleantech asking for some clarification.

My initial impression is that, even with the decline, there’s still a ton of money going into clean tech overall.

How would you characterize clean tech investment trends? Would love your input.