Measuring site performance is vital. Yet many of us have trouble understanding exactly what should be measured. Obviously, an essential key performance indicator (KPI) for all sites is conversion rate. In addition to overall conversion rate, there are two others. Let’s explore all three:

• Overall conversion rate: Total number of actions considered conversion divided by total number of visits. This is a site’s overall effectiveness rating for getting visitors to fulfill your goals within a single visit.
• Scenario conversion rate: Total number of visitors starting a specific scenario divided by total number who complete it. Scenario conversion rates enable you to quickly identify specific conversion processes that require improvement or ones whose successes should be modeled.
• Conversion over time: Several measures that reveal a site’s effectiveness in generating conversions over time. Use this for situations where conversion is likely to occur over time or multiple visits.

Overall Conversion Rate

Overall conversion rate accounts for people having numerous goals when visiting a Web site. Probably you do, too. It provides a more accurate picture of how effectively a Web site serves people and accomplishes your goals on a per-visit basis.

Generally, it should be used only to evaluate broad, sweeping changes. Use it to evaluate the results of a site redesign, a specific marketing campaign, or new site-search technology.

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