Question: There are two competitive ways to present these confidence intervals.

Method 1

point estimate ± margin of error

The margin of error is the quantity E.

Method 2

Or alternatively... (lower limit , upper limit)

The upper limit is the point estimate + margin of error.

The lower limit is the point estimate - margin of error.

Depending on the field, one or both of these methods may be in common use.

Find confidence intervals for the unemployment rates in 2000 and 2003. Then present both intervals by both methods. A confidence interval is called an "interval estimate".