It might be worth looking at your super's product disclosure statement (pds). You can simply google 'super name' pds. Should come up with it. Otherwise just type pds in the search bar of your super's website. Here is an example of one from Australian Super's diversified fixed interest:
So international bonds will come with exchange rate risk, and the active investment means that bonds will be bought and sold a lot, each will have a different coupon rate and so this could add to the change also. Another thing to think about is that supers don't invest 100% of the funds under management. They need cash for liquidity. So the daily cash vs bond mix will affect your daily return
Just another snip talking about the mix of bonds.
