Chase Van Der Rhoer, a Bloomberg application specialist, makes the case for an investment bubble in this morning?s Bloomberg brief:

Bubbles don?t exist without investment funds crowding into the same trades relative to liquidity. Researchers will often construct measures of market-crowding such as the ratio of the Nasdaq Composite Index price to the relative amount of volume. This ratio has increased 238% since 2009 ? showing cause for concern.

And here?s his chart: