A portfolio generates the following returns over the past 10 years:

Year	Return (%)
1	-17
2	11
3	11
4	22
5	-18
6	-10
7	19
8	2
9	3
10	15

Calculate the test statistic to test whether the standard deviation of this portfolio's return is different from the benchmark portfolio standard deviation of 23.

Enter answer accurate to 3 decimal places.

Bonus thinking question: can you reject the hypothesis that the two standard deviations are equal? (use the CHISQ.INV() spreadsheet function to find the rejection points for your desired test probability)