This may be a naïve question but I have read in several sources (example) that calculating the relative standard deviation is unreliable if the mean is close to zero.

Suppose my replicate values are as follows (n = 12):

Data points: 0.1223, 0.1251, 0.1302, 0.1287, 0.1211, 0.1195, 0.1338, 0.1240, 0.1263, 0.1252, 0.1279, 0.1216

Thank you!

**My questions are:**

1.)How close should the mean be to zero before RSD(%) becomes unreliable for expressing statistical spread?1.)

**2.)**Would RSD % be suitable for a set of data such as the one shown below:Suppose my replicate values are as follows (n = 12):

Data points: 0.1223, 0.1251, 0.1302, 0.1287, 0.1211, 0.1195, 0.1338, 0.1240, 0.1263, 0.1252, 0.1279, 0.1216

**Sample mean:**0.1255**Sample standard deviation:**0.00416**Skewness:**0.5134**Kurtosis:**-0.1534**D'Agostino & Pearson omnibus normality test (alpha = 0.05)?**Passed? Yes**Relative standard deviation:**3.32%Thank you!

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