As calls for a US economic recession mount, it can be difficult to separate between the informed predictions and those that are simply piling on. In an exclusive interview with Business Insider, Brad McMillan — the chief investment officer of the $150 billion Commonwealth Financial Network — shared his four-part recession checklist for investors to watch. While the economy still has a ways to weaken, by the four measures outlined by McMillan, it's edging closer to troublesome territory. As calls for an US recession mount, it's an easy time to pile on with vague platitudes about an impending economic meltdown.