A large project, such as construction of a major highway or development of a large mine will have a significant impact on the economy. The spending in the construction and operating phases will generate income and employment, and public sector decision-makers often take these effects into account in deciding whether or not to undertake the project. An economic impact analysis is a different procedure from a cost-benefit analysis in that it attempts to predict, but not evaluate, the effects of a project. Keynes is reputed to have observed that digging a purposeless hole in the ground or building a hospital might have the same economic impact but very different levels of net benefit. Since the data assembled in the course of a CBA are often used as inputs to an economic impact analysis, the two types of analyses tend to be related in the minds of decision-makers and may be undertaken by the same group of analysts.