For a similar period as Jaiml's for OVTI, that spreadsheet is showing figures of
when VFISX is used for cash
If you scan down the trade $ amounts column you'll see the + (buy) and - (sell) trade amounts. Ocroft's idea is to accumulate all AIM buy trades and only actually buy after AIM stops buying. For the sequential buys shown in that spreadsheet you can scan across and see the price that all of that $$$ amount of buy trades would have bought more stock at. Typically when there are sequential buys lumping them all in at the price after the last buy trade was indicated by AIM will average in at a better (overall lower) price. In some cases - typically when just a single buy trade is indicated having waited results in buying at a worse (higher) price. Broadly however it would seem that the cost of buying single trades at often higher prices than had you religiously followed AIM is more than compensated by buying larger amounts (several buy trades in a row) at a lower overall average price when several sequential AIM buy trades occur in a row. That's also less risky as cash is preserved for longer before being deployed.
Now a couple of questions. Is the function of the VFISX to allow the inclusion of the changes to your cash reserves because it is held there? If so, why do you use the adjusted price? It would seem to me that when you put money in, say $5k, on one day at a price of $10/share, or 500 shares, and then when you want to draw some to fund a buy the number of shares you need to sell would determined by the actual trade price, say it was $10.20 and you needed $3k, then you would sell 294.11 shares.
As an example, in all of June and July of 2000, the open price and intraday never got lower than $9.98 and the intraday as well as the close never got above $10.03 yet the adjusted close ranged from $6.35 to $6.43. It would seem to me that if you bought on July 14th, 2000, you would have paid exactly $10.01 as it did not vary at all and if you sold it on July 31st, 2000, you would have gotten $10.02/share, not the adjusted close of $6.42.
What am I missing?
BTW, one of the things that has annoyed me about the way Yahoo displays the prices for the month is that they use the date for the first trade of the month but the price is actually for the last close of the month.