0 - I have no idea what SEO means
1 - I have heard of SEO but I don't know what it is
2 - I have heard of SEO and I know the definition of it
3 - I have heard of SEO but my knowledge is limited
4 - I am decent at SEO optimization
5 - I have good knowledge of SEO but I am not good at optimizing content
6 - I have good knowledge of SEO and I am good at optimizing content
7 - I am great at SEO optimization but there are things I still need to learn
8 - I am a SEO professional with 1+ years of Search Engine Optimization experience
9 - I am a SEO professional with 3+ years of Search Engine Optimization experience
10 - I am an SEO expert (consultant level) with 5+ years of Search Engine Optimization experience