= Relative risk bounds from rounded group compositions
{title2=$\dfrac{a_L(1-p_U)}{p_U(1-a_L)}\leq\operatorname{RR}\leq\dfrac{a_U(1-p_L)}{p_L(1-a_U)}$}
Suppose $0<p_L\leq p\leq p_U<1$ and $0<a_L\leq a\leq a_U<1$. The formula for <relative risk from group compositions> increases with $a$ and decreases with $p$, since $a/(1-a)$ increases and $(1-p)/p$ decreases. This <monotonicity> proves the displayed bounds. If percentages are rounded to the nearest whole percentage point, each corresponding proportion lies within $0.005$ of its displayed value. These bounds describe rounding uncertainty; they are not a <confidence interval> for sampling uncertainty.
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