You calculate the following monthly returns for the S&P500 Stock Index, the S&P500 Bond Index, and the MSCI World excluding US Stock Index

Date	S&P 500 Stock	S&P 500 Bond	MSCI World ex US
29-Jan-22	-1	-1	-1
26-Feb-22	3	-2	2
31-Mar-22	4	-2	2
30-Apr-22	5	1	6
28-May-22	1	1	-1
30-Jun-22	2	2	1
Average	2	0	2

Fill in the missing values needed to calculate the covariance between the S&P 500 Stock Index and the S&P 500 Bond Index is:

(1/ )*[(-1-2)(-1-0)+( -2)(-2-0)+(4- )(-2-0)+(5-2)(1- )+(1-2)(1-0)+(2-2)( -0)]