The neoclassical investment literature assumes that capital is homogenous, lives forever and has a constant depreciation rate. More recent theories of investment have shown that when there are distinct capital vintages with embodied technologies, depreciation and capital retirement become...

This paper estimates the micro-level costs of adjusting capital using detailed data onquot; investment decisions in the US airline industry. The data include the capital stock retirement, market values, operating costs, and utilization rates of 16 different types of capitalquot; goods for each...