[squiffy]

So, assuming the entire 2400 has been earning interest. (The last $300 deposit only for 1 month)

200 profit / 2400 invested = about 8.3% but not per annum.

I think the key to keep in mind is that you are doing better than 8.3% per annum because 8.3% per annum would mean that you put the entire 2400 in on Jan 1 and kept it there for 12 months.

Here, 1 $300 deposit was only there 1 month, 1 $300 deposit was only there 2 months, 1 $300 deposit was only there 3 months, etc.

Again, it may NOT be helpful or realistic to translate this earning into any other kind of per annum analysis, because as I illustrated with the stock, that would be speculative.

Who knows what will happen to the last $300 deposit over 12 months.

So I would keep it simple and stick to the basic facts.

You deposited $2400 over the course of 1 year. At the end, you have $200 more than when you started.

So you have actually made 8.3% on the money invested. Though not per annum. You can recalculate at the end of each month or year. As long as you are consistent in your calculations, you can follow roughly how you are doing.

The good thing about a stock purchase is that it is easier to figure out how EACH purchase is doing, because you have a purchase price and the number of shares, and you can compare to the current market price.

So last year, I made about 12-15 separate purchases of NOK. Some purchases were at say $12 and the stock went up to say $16.

Other purchases wer at 16.50 and the stock was underwater.

So I did separate calculations for each purchase. Some purchases were profitable and some were not.

And I also did a grant total, lumping together all the purchases and coming up with a profit percentage. And I used the earliest purchase date.

So, I started buying in Jan. and kept buying through Dec.
At the end I had $45,000 more than I had in Jan.

SO that is NOT a per annum profit because some of the purchases had only been held for 1-2 months. But just for the purpose of rough calculations, it was somewhat akin to a giant single purchase in Jan.