Enter the total number of words read and the total number of errors made into the calculator to determine the error rate in scoring and analyzing a running record.

## Error Rate Formula

The following formula is used to calculate an error rate.

ER = TW / TE
• Where ER is the error rate
• TW is the total words
• TE is the total errors

To calculate an error rate, divide the total number of words by the total number of errors.

## Error Rate Definition

What is an error rate? An error rate, in the context of reading, is a ratio of the total words read to the total errors made while reading. This is used when scoring and analyzing a running record of an individual.

## Example Problem

How to calculate error rate?

1. Frist, determine the number of words read.

For this example, the student read 500 words.

2. Next, determine the number of errors.

While reading, their were 50 recorded errors.

3. Finally, calculate the error rate.

Using the formula above, the error rate is found to be 500/50 = 10:1.