Table 4.
Variances comparison before 2012, between 2012 and 2019 and after 2020
| Until Dec/2011 | 2012–2019 | Ratio | 2020 | Ratio | Levene test | |
|---|---|---|---|---|---|---|
| S&P 500 | 1.431 | 0.655 | 0.457 | 4.925 | 7.525 | 109.08 (0.000) |
| DJIA | 1.365 | 0.635 | 0.465 | 5.616 | 8.848 | 128.39 (0.000) |
| NASDAQ | 2.135 | 0.938 | 0.439 | 5.248 | 5.598 | 84.59 (0.000) |
| 8.737 | 3.193 | 0.365 | 8.606 | 2.695 | 61.66 (0.000) | |
| AMAZON | 19.202 | 3.459 | 0.180 | 5.985 | 1.730 | 243.99 (0.000) |
| TESLA | 13.910 | 9.749 | 0.701 | 32.523 | 3.336 | 63.98 (0.000) |
| APPLE | 9.611 | 2.604 | 0.271 | 8.830 | 3.391 | 178.23 (0.000) |
| NETFLIX | 17.029 | 9.239 | 0.543 | 8.649 | 0.936 | 37.78 (0.000) |
| 5.033 | 2.123 | 0.422 | 6.021 | 2.836 | 79.67 (0.000) |
Ratio is the division of the variance from two different periods. For example, the ratio after column “2020” divides the returns’ variance of the year 2020 by the variance of the period 2012–2019. The columns “Until Dec/2011”, “2012–2019” and “2020” include the variance for each period. Levene test p value is in parenthesis