Success rate is a term used in statistics that you can apply to many different areas. The success rate looks at a data sample where you have either successes or failures, such as did a mother give birth or not. The opposite of a success rate is the failure rate. If you add the success rate to the failure rate, then it will equal one because the data is set up to give two responses: success or failure.

Determine the total number of attempts in your sample. For example, assume you flip a coin 100 times.

Find the number of successes you have in the sample. In the example, assume getting the coin to show "heads" is considered a success. The coin comes up heads 56 times.

Divide the successes by the total number of attempts to find success rate. In the example, 56 divided by 100 equals 0.56 or 56% success rate. Therefore, the failure rate is 44%.