Vanguard's IRR seems to be much higher than I'd expect

[chucky16]

@newcreation17 I think the explanation might be the money you've taken out of the account. You don't mention including withdrawals in your own calculations of IRR.

 

[newcreation17]

@chucky16 I haven't taken any withdrawals!

I think the explanation is as in another comment: even though Vanguard themselves refer to IRR in calculating it, it's not actually a "rate" because they don't annualise it. Instead it appears to be the value IRR[sup]number of years since inception of account[/sup] .

So if you want an actually useful figure (I e., one that is a "rate" because it's annualised), you should take the figure Vanguard gives and raise it to the power (12/n), where n is number of months the account has been open.