This paper argues that the future of capitalism depends mainly on the rate of profit. Updates of previous estimates of the rate of profit are presented which show that the rate of profit has recovered only about 40 percent of the prior decline in the rate of profit during the 1960s and 1970s, thus suggesting that the current stagnation in the U.S. economy is likely to continue in the foreseeable future. It is argued that the main reason for the lack of a more significant increase in the rate of profit is a continued increase in the relative proportion of unproductive labor.