Some time ago, as the B share, which was approaching a discount, continued to fall by the limit, some investors sold B shares by buying A shares and redeeming them together. The demand for A shares pushed its price upward. In addition, for investors who are bearish on the market outlook, Class A shares of index funds can be used as a good "put option" for investment.

From the beginning of June to the present, the implied yield of grade A has dropped from 6.8% to 5.8%, the price has increased by about 15% on average, and the implied yield has reached the lowest level since 2012. On the one hand, A has low value as a bond allocation. On the other hand, the value of "put options" is no longer as good as it used to be, and the value of put options cannot continue to drive Class A prices to continue to rise.

Therefore, Class A has no comparative advantage over bonds.