Economic expansions usually don't go on for this long

We're in one of the longest economic expansions in the last 100 years

72 months to be exact. That's way above the median length of 37 months.

In fact, KKR's Henry McVey believes that the US economic cycle right now is "somewhere between its middle and later stages." And that means it may be prudent for investors to scale back on some risk.

"In our humble view, now is the time ... to start peeling back some of the more speculate positions in one's portfolio," McVey writes.

KKR