Related to mindcrime's comment, with data points updated monthly, there is a lot of volatility in that graph and it's hard to draw conclusions. While having that drastic a drop isn't inspiring news, it could be due to a number of factors. To her credit, Danielle does not add her own causation theories and merely quotes the NVCA's.

My point is that if next month jumps back to a number closer to recent trends, the last month could easily be an outlier.

Now, if there is a continued depressed trend in startup investments over the next six months, one could put forth a convincing case that new tax laws and problems in the Euro-zone (as NVCA suggests) are hurting startup investments.