FYI: There are many definitions and rules of thumb in the finance world. Most are arbitrary since the markets are more art than science. People often throw around terms without providing justification or context. “Bond bear markets” seem to fall under this category. In this piece I wrote for Bloomberg I discuss why a bond bear market is an entirely different animal than a stock bear market and why there really is no workable definition.
Regards,
Ted
http://awealthofcommonsense.com/2018/03/what-is-a-bond-bear-market-anyways/