eileen-code4fun / ACBCalculator

ACBCalculator

This calculator takes a CSV file of stock transaction logs and produces the report of adjusted cost-base and gain.

Adjusted cost-base is a method to calculate rolling average price of a stock. For example, if you buy stock 5 shares of stock A at price 100, then you buy another 5 shares of stock A at prince 200 again. Your ACB average price of stock A is (5*100+5*200)/(5+5)=150. When you sell 6 shares of stock A at price 300, your gain is (300-150)*6=900.

The calculator expects the following format in the CSV file:

Date	Stock	Action	Unit	Price	Commission	Ex
2018-05-12	GOOG	Buy	10	700	3.5	1
2018-07-23	MSFT	Buy	10	300	0	1.2
2019-11-10	APPL	Buy	5	200	2.4	1.3
2019-11-12	AMZN	Buy	10	2000	5.6	1.32
2019-11-15	APPL	Sell	2	210	0	1.4
2020-01-05	APPL	Buy	2	205	0	1.3
2020-02-02	APPL	Sell	5	300	0	1.23
2020-02-03	AMZN	Sell	8	3000	0	1.4
2020-03-12	GOOG	Sell	5	1700	0	1
2020-04-23	MSFT	Sell	10	250	0	1.2

• Date column should be in the format of YYYY-MM-DD.
• Stock column contains the stock symbol.
• Action column contains either Buy or Sell.
• Unit column contains the number of shares in that transaction.
• Price column contains the unit price of that stock in that transaction.
• Ex column is optional. It contains the exchange rate of that date. The default is 1.

Other columns may be included in the CSV file but they'll all be ignored.

# Run the calculator:
$ python main.py sample.csv
# Sample output:
$ GGain: {2019: {'APPL': 66.75199999999995}, 2020: {'GOOG': 4998.25, 'AMZN': 12474.0864, 'APPL': 530.1279999999999, 'MSFT': -600.0}}