Calculate historical inventory value over time from current inventory value

So, it would be working backwards from the Total Valuation in the first table using the transactions amount from the second table so you can see the Historical Total Value for each date. Note that this means the negative numbers would add back into the value as you go into the past. So for Part 1, it would like this:  

The bottom row added the 1053.87 to the current 1000, then the next adding the 450.31 back and so on.