Key Performance Indicators (KPIs) help organizations to achieve organizational goals through the definition and measurement of progress in Web World. The key indicators are agreed upon by an organization which can be measured that will reflect success factors. The KPIs selected must reflect the organization's goals, they must be key to its success, and they must be measurable. For natural search channel programs , I think the following indicators are helps to analyse the web performance:
1. Unique Pages
2.Brand to Non-Brand Mix
3.Pages Yielding Traffic means Organic Visits Per Page
4.Keywords per Page Yield
5.Engine Yield
6.Index-to-Crawl Ratios
7.Visitor per Keyword Yield means Conversion Rate Per Keyword
8.SERP Rankings for High Volume Keywords
To know more, I recommend Steve Jackson Series & The true value of SEO KPIs by Joe Bursell