At the start of the overnight session (yesterday night), 10yr yields were up around 1.58%.  By 1030am ET, they'd already fallen to 1.525%.  Up until that time, we hadn't heard so much as a peep out of global equities markets even though they would go on to get credit for the day's big move in bonds.

If you're picking up what I'm layin' down here, the point is that bonds were already most of the way to their destination well before stocks had a chance to exert influence.  Nonetheless, the stock swoon in the 11am hour managed to impress.  The S&P lost more than 40 points in short order and bond yields were compelled to plumb new lows for the day, even if those lows were only 2bps below the morning's best levels.  

Although coronavirus headlines got a lot of attention as the culprit behind the market movement, we can't really rule out a simple late-day sell-off in European equities markets.  Case in point, note the behavior in the DAX heading into its closing bell and the fact that US equities bounced precisely when that bell rang.

None of this is material to the bigger picture, however, as we'd need to be seeing yields make a much sharper move up and over 1.67% before we'd consider the bond market to be doing anything other than consolidate February's coronavirus gains.  Limited econ data tomorrow.