Theory also teaches that the increase in the rate of return on capital--even if generated by a rise in the growth rate of technical change--ultimately requires an increase in real market interest rates. Market interest rates must rise in order to maintain equilibrium between the higher demand for investment funds and the supply of investment funds.
And, indeed, we have seen that market interest rates, particularly for corporate issuers, have risen steadily for the last year or so. Interestingly, rates of return for forms of capital other than computer equipment, including both structures and non-computer equipment, either have not increased or have not risen as much as the rates of return on their high-tech counterparts.