You are interested in investing in Australian shares and decide to investigate the shares of two Australian companies: Afterpay Limited (APT.AX) and Commonwealth Bank of Australia (CBA.AX). Below are the opening prices, closing prices for APT and CBA for 2020 and dividends paid by CBA during 2020. APT did not pay any dividends in 2020.

	APT		CBA
Month	Opening Price	Closing Price	Opening Price	Closing Price
Jan	29.28	38.55	72.70	85.26
Feb	37.57	33.17	74.38	81.78
Mar	32.18	18.80	71.24	61.82
Apr	19.85	31.20	71.13	62.69
May	29.75	47.41	69.30	63.75
June	46.53	60.99	72.06	69.42
July	60.49	68.54	72.39	71.20
Aug	68.50	91.44	69.23	68.28
Sep	89.80	79.99	73.95	63.61
Oct	81.85	96.69	71.00	69.02
Nov	96.50	95.01	74.81	79.07
Dec	95.80	118.00	78.06	82.11

Dividends	19/02/2020	15/08/2020
CBA	2.00	0.98

For the rest of the question please show relevant formulas and all calculations.

5. Calculate the correlation coefficients between APT and CBA. 1 marks