Margin of error represents the level of accuracy that a random sample has achieved, and applies wherever a representative sample is surveyed. The larger the margin of Error, the less confidence you should have in how closely the views expressed by the sample represent the views of the target population as a whole.
MOE with Finite Population Correction Factor = (z-score)sqrt[p(1 − p)/n] × sqrt[(N − n)/(N − 1)]
N = population, n = sample size, p = 0.5 (normal distribution)
90% − Z-Score = 1.645
95% − Z-Score = 1.96
99% − Z-Score = 2.576