Financial Glossary
Year-Over-Year (YOY)
Year-Over-Year (YOY) is a method of evaluating financial or operational performance by comparing a specific period in the current year against the identical period in the prior year. Because it controls for seasonality, YOY isolates organic growth from calendar effects. It is applied to revenue, expenses, bookings, headcount, and any time-series metric. The comparison is expressed as a percentage change: ((current period value minus prior period value) divided by prior period value) multiplied by 100. Analysts prefer YOY over sequential comparisons when demand is cyclical.
Problem & Application
Consider a campground that earned $180,000 in revenue during the summer quarter this year versus $150,000 in the same quarter last year. YOY growth is ($180,000 minus $150,000) divided by $150,000, or 20%. That figure is meaningful because both periods share the same seasonal pattern. A sequential comparison to the prior winter quarter would show an apparent jump driven entirely by seasonality rather than business momentum. However, a single strong YOY number can mislead if the prior-year period was distorted by an unusual event such as a road closure, a COVID restriction, or a one-time group booking. Best practice is to annotate YOY figures with any known prior-year anomalies, segment the metric by same-store versus new-site cohorts, and pair it with a multi-year trend so a recovery from a weak base is not mistaken for sustained acceleration.
In Short
YOY is a valuable metric for evaluating growth trends. By comparing performance against the same period in the previous year, companies can assess overall progress and identify key areas for improvement.