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Negative Z Score Table

negative Z score value indicates the raw score value is either left or below the mean of the standard normal distribution.

The negative z score in the z-table represents the area under the bell curve to the left of z.

If the z score value is negative, use the negative z table to find an area on the left of the mean of the distribution.

You can refer Z score calculator article which explains how to calculate the Z score using the z score formula below

z = (x -μ )/σ

μ = is the population mean for the unstandardized value
σ = is the population standard deviation for the unstandardized value
x = is the raw score value

z = is the calculated z-score value.

In this tutorial, we will discuss negative z score, and how to read a negative z score chart with examples.

Negative Z-Score Table

A negative z-score value is either left or below the mean of standard normal distribution.

A negative z-score table has values less than 0.

Negative Z Score Chart

Negative Standard Normal Distribution Table

This negative z score table having a z value between 0 to -3.4 represents the area under the bell curve to the left of z.

How to Find Negative Z Score on Z Table?

To understand how to use a negative z-score chart, let’s take an example.

Find the z-score based on the below information

  • Mean: 71
  • Standard deviation: 4
  • Raw score: 68

To find the z-score, use below z-score formula.

z = (x – μ )/σ


x = raw score

μ = mean of the data set

σ = standard deviation of the data set.

Use the input parameters in the z-score formula

z = (68-71)/4

z = -0.75

Z-Score for a raw score of 68 is -0.75. This means that the raw score of 68 is a 0.75 standard deviation below the mean of 71.

The Z-score value is negative, hence use the negative z-score table to find the area.

Negative z-score chart
Negative z-score chart

Using the above negative standard normal distribution table, the area for a negative z-score value of -0.75 is 0.2266 as marked in yellow color.

The corresponding area for z-score -0.75 is 0.2266 which is 22.66%


I hope the above article on how to use a negative z-score table with an example is helpful to you.

You can find more topics about Z-Score and how to calculate the z score given the area on the ZScoreGeek home page.

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