擺到期可以收返本金+息
個分別就係呢句,隨住你 hold 個直債越嚟越接近到期,個 effective duration (sensitivity to interest rate) 會下跌,但以asset allocation 嘅角度嚟講咁做係唔合理,因為你會想維持既定嘅 effective duration 去 hedge 股票(effective duration越大通常 hedging 效果越好,因為股災會減息),bond ETF 就係不停去 roll 新嘅債以維持既定嘅 effective duration
債 ETF 價跌但 yield 會升,時間夠長你收多咗嘅息就可以彌補返跌咗嘅價,所需嘅時間大概就係個 effective duration, 所以只要你 hold 個 bond ETF 嘅時間係長過佢嘅 effective duration,加減息其實唔太關你事