There are two main reasons why the AUV reported in Morningstar Office is different than the AUV on your account statement. While the AUVs may differ, the returns will be the same.
There are multiple pricing bands and multiples series of AUVs for each annuity reflecting differing distribution channels, M&E's, optional ryders, etc. Morningstar may cover one series and only at the highest M&E. You may own another series, possibly with a slew of option ryders added on. This causes the AUVS to mismatch. Say the series Morningstar covers changes from $10 to $20 in a certain period. Your series changes from $20 to $40 in the same period. Different "prices", same return.
There are only approximately 50,000 distinct subaccounts. However, there are more than 9 million pricing bands of them. As you can see, statistically, we are not going to match most of the time. Our returns are correct, though. Similarly, this would be like saying our stock data are wrong because our returns don't match a client's personal price net of the brokerage commission he paid. Or a fund client saying that our returns don't reflect the fact that she got a partial load waiver from her broker down to 2.5% and we only show returns as net of or including the max 5% load.
Insurance companies constantly switch the underlying funds they use/offer in a particular policy. If Robertson Annuity on 5/1/2005 changes from using ABC Value VIP Fund to XYZ Value VIP Value Fund, we will:
Create a new subaccount with an inception date of 5/1/2005
Call it Robertson Annuity XYZ Value VIP Value
Calculate pre-inception returns going back to the inception of the earliest share class of XYZ Value VIP Value
The client's statements may reflect his personal rate of return, which is a mixture of the performance of the two different underlying funds. Our pre-inception data reflects a hypothetical history based on the fund currently used.