Diagram showing a symmetric bell curve with x-axis values of negative 2, negative 1, zero, one, and two. The area under the zero to one curve encompasses 34.1%, which is also mirrored by the zero to negative one curve. The next values between one and two include 13.6%, also mirrored by the negative side. The area between negative one to one is 68.2%. The area encompassed by all four bins includes 95.4%.