# What is YoY? Definition & Technical Mechanics

> **Source:** [SPIDITS AI Startup & Venture Intelligence Glossary](https://spidits.com/startup-glossary)  
> **Category:** Metrics  
> **Canonical Citation:** [https://spidits.com/startup-glossary/yoy](https://spidits.com/startup-glossary/yoy)

## Definition
YoY (Year-over-Year) is a growth metric that compares a financial or operational performance measure in a specific period to the exact same period in the previous year.

## Architectural Mechanics & Deep Dive
YoY (Year-over-Year) is a growth metric that compares a financial or operational performance measure in a specific period to the exact same period in the previous year, eliminating seasonal variations.

## Industry Applications & Real-World Use Cases
Annual growth velocity and seasonality analysis

## Frequently Asked Questions

### Why is YoY growth preferred over MoM growth?
YoY eliminates seasonal variations (e.g. slow sales in December) to show true underlying annual growth.

### How is YoY growth calculated?
YoY = ((Current Period Value - Previous Year Period Value) / Previous Year Period Value) x 100.

## Related Terminology
- [arr](https://spidits.com/startup-glossary/arr)
- [run-rate](https://spidits.com/startup-glossary/run-rate)
- [traction](https://spidits.com/startup-glossary/traction)

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*From the SPIDITS AI Knowledge Base (311+ terms indexed). Explore full technical definitions: [https://spidits.com/startup-glossary](https://spidits.com/startup-glossary)*