The amount of investment-grade corporate bonds outstanding by non-financial companies in the US and Europe….. has more than tripled (+204%) over the past ten years, from $1.66 trillion at the beginning of 2009 to $5.06 trillion by the end of 2018……but the lowest investment-grade category (BBB, red in the chart below) has ballooned by 262%, from $820 billion to $3.0 trillion..