Answer: 0.23%

## Explanation To calculate the standard deviation of the mean (also known as the standard error), we use the formula: **Standard Error (SE) = (Standard Deviation) / √n** Where: - Standard Deviation = 1.8% - n = number of observations Since the analyst has collected monthly data for five years: - n = 5 years × 12 months/year = 60 observations **Calculation:** SE = 1.8% / √60 SE = 1.8% / 7.746 SE = 0.2323% ≈ 0.23% **Key Points:** - The standard error measures the precision of the sample mean as an estimate of the population mean - As sample size (n) increases, the standard error decreases - This is a fundamental concept in statistics for understanding sampling variability - The mean monthly return of 6% is not directly used in this calculation, as we only need the standard deviation and sample size

Author: Tanishq Prabhu