Sorry, folks, my terminology is rusty, so I lack the correct mathematical terms to describe my question. This will be in plain English.
The question is find a formula that describes the progression of quantities to purchase at regular decreasing price intervals while maintaining 60% average purchase price.
This relates to theoretical plan is to purchase an asset at price X and take profit if the prices goes up. However, if it goes down then progressively purchase at decreasing sizes to retain a 60% average purchase price between highest and lowest price.
Using the formula, it can be solved for A) the quantity to purchase at a new price. Or B) given a quantity, at what exact price to purchase to maintain 60% average?
Here's an example and clarification of the 60% average:
1000 at $10.00 ==> 1st purchase 666 at $ 9.00 ==> 2nd purchase Average purchase price is now $9.60 or 60% between highest and lowest price. 555 at $ 8.00 ==> 3rd purchase. Average $9.20 or 60%. 493 at $ 7.00 ==> 4th purchase. Average $8.80 or 60%
So what is formula to describe the progression:
1000, 666, 555, 493, and so on.
By the way, those aren't perfectly 60% above, there all a small fraction over 60%.