Annual Failure Rate Formula

Annual Failure Rate Formulaの概要と注目ポイントをわかりやすく整理しました。

At its core, AFR is a percentage. It tells you how many products from a batch will fail within one year of use. The formula is: AFR = (Number of Failures / Total Units) × 100%.

Imagine you buy 100 light bulbs. After a year, 5 stop working. Your AFR is 5%. That’s it—no rocket science, just a neat little ratio.

But wait, it gets cooler. AFR doesn’t just count failures; it sneaks in time as a secret ingredient. It’s not just “how many broke?” but “how many broke in exactly 365 days?”

Why Should You Care?

Because everything around you has a failure rate. Your car’s engine? Yep. Your coffee maker? Oh, absolutely. AFR is the silent narrator of your stuff’s lifespan.

Ever gotten frustrated when a product dies right after the warranty ends? That’s manufacturers using AFR to time those warranties perfectly. They know the number, and now you can too.

Here’s a fun comparison: Think of AFR like a weather forecast. Just as a 30% chance of rain doesn’t mean it will pour everywhere, a 5% AFR doesn’t mean your exact device will fail. It’s a probability, not a promise.