(a) General. We consider that work exists in the national economy when it exists in significant numbers either in the region where you live or in several other regions of the country. It does not matter whether—
(b) How we determine the existence of work. Work exists in the national economy when there is a significant number of jobs (in one or more occupations) having requirements which you are able to meet with your physical or mental abilities and vocational qualifications. Isolated jobs that exist only in very limited numbers in relatively few locations outside of the region where you live are not considered work which exists in the national economy. We will not deny you disability benefits on the basis of the existence of these kinds of jobs. If work that you can do does not exist in the national economy, we will determine that you are disabled. However, if work that you can do does exist in the national economy, we will determine that you are not disabled.
(c) Inability to obtain work. We will determine that you are not disabled if your residual functional capacity and vocational abilities make it possible for you to do work which exists in the national economy, but you remain unemployed because of—
(d) Administrative notice of job data. When we determine that unskilled, sedentary, light, and medium jobs exist in the national economy (in significant numbers either in the region where you live or in several regions of the country), we will take administrative notice of reliable job information available from various governmental and other publications. For example, we will take notice of—
(e) Use of vocational experts and other specialists. If the issue in determining whether you are disabled is whether your work skills can be used in other work and the specific occupations in which they can be used, or there is a similarly complex issue, we may use the services of a vocational expert or other specialist. We will decide whether to use a vocational expert or other specialist.