Return Risk 293072
1. **Problem Statement:** Calculate the return and risk (standard deviation) of each stock ALI, TEN, and BOC from 2016 to 2024.
2. **Formula for Return:** The annual return $R_t$ for year $t$ is calculated as
$$R_t = \frac{P_t - P_{t-1}}{P_{t-1}}$$
where $P_t$ is the price at year $t$ and $P_{t-1}$ is the price at the previous year.
3. **Formula for Risk (Standard Deviation):** The risk is the standard deviation of the returns:
$$\sigma = \sqrt{\frac{1}{n-1} \sum_{t=1}^n (R_t - \bar{R})^2}$$
where $\bar{R}$ is the mean return and $n$ is the number of returns.
4. **Calculate Returns for Each Stock:**
- For ALI: Calculate returns from 2017 to 2024 using prices from 2016 to 2023.
- For TEN: Similarly calculate returns.
- For BOC: Similarly calculate returns.
5. **Example Calculation for ALI Returns:**
$$R_{2017} = \frac{63.8 - 60}{60} = 0.0633$$
$$R_{2018} = \frac{66 - 63.8}{63.8} = 0.0345$$
... and so on for all years.
6. **Calculate Mean Return $\bar{R}$ for Each Stock:**
Sum all returns and divide by number of returns (8 years).
7. **Calculate Standard Deviation $\sigma$ for Each Stock:**
Use the formula above with the returns and mean return.
8. **Summary of Returns and Risks:**
- ALI: Mean return $\bar{R}_{ALI}$ and standard deviation $\sigma_{ALI}$
- TEN: Mean return $\bar{R}_{TEN}$ and standard deviation $\sigma_{TEN}$
- BOC: Mean return $\bar{R}_{BOC}$ and standard deviation $\sigma_{BOC}$
**Final numerical results:**
- ALI returns: [0.0633, 0.0345, 0.1682, -0.0635, 0.0964, 0.0762, -0.1774, 0.05]
- ALI mean return $\bar{R}_{ALI} = 0.0379$
- ALI standard deviation $\sigma_{ALI} \approx 0.096$
- TEN returns: [0.1533, 0.0145, -0.0714, 0.04, 0.0686, 0.1385, -0.0273, -0.14]
- TEN mean return $\bar{R}_{TEN} = 0.0229$
- TEN standard deviation $\sigma_{TEN} \approx 0.091$
- BOC returns: [-0.1321, 0.0741, 0.1797, 0.2292, 0.0158, -0.067, -0.025, 0.0486]
- BOC mean return $\bar{R}_{BOC} = 0.0332$
- BOC standard deviation $\sigma_{BOC} \approx 0.111$
These calculations provide the return and risk for each stock based on the given data.