The declines in global bond markets this week points out the need to be aware of your bond ETFs duration, which measures the sensitivity of the bond or ETF to changes in interest rates. Duration is expressed in years, and the longer the duration, the greater the change in the price of the bond (or bond ETF) for a given change in interest rates. You may also own bond clones, or ETFs which are closely linked to the bond market, such as an ETF with utilities. Since such funds have stocks, there is no way to know their effective duration. I looked at the universe of Vanguard bond ETFs to i