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12 Outlook on further developments. In this paper the idea has been elaborated that the amount of wealth determines the chances of having certain amounts of income.But it may be thought that also the inverse relation - influence of income on wealth - plays a role. Certainly the increment of wealth per year depends on income,given the rate of saving out of various incomes. If we take into account that the present income is usually strongly correlated with the past incomes of the same person,or even of his ancestors, then it appears that the chances of a certain wealth may be determined,indirectly, by the present income.And we may connect this relation with the regression line of wealth on income (which in the Swedish data appears so very distorted on account of the truncation of the distribution). There are,then, two theories ,and two regression lines. It would be very convenient if we could regard each of the regression lines as a true picture of the corresponding theory. This correspondence is,however,marred by the greater or lesser dispersion of values round each of the regression lines. It can easily be seen that the dispersion round one of the regression lines will influence the shape of the other regression line. If the rate of return of a given wealth is widely dispersed then the persons with a high rate of return will be classified in the high income classes,those with the same wealth but with a low rate of return among the small incomes. This will more or less strongly counteract the tendency of wealth to increase with income, it will flatten out the regression line. It seems to me that the joint distribution of two variables like income and wealth should be approached from the standpoint of a more elaborate theory. One could imagine a stochastic process,in the simplest case a Markov chain, in two stages: One matrix would show for each amount of wealth at the beginning of the year the probabilities of various incomes in that year. Another matrix would show for each of these incomes the probability of wealth at the end of the year - which results from the addition of the saving out of the various incomes to the initial wealth.In this way both parameters,the rate of return on wealth and the rate of saving out of income, would play their role in the process. A multiplication of these matrices would describe a continuing process of accumulation,starting from certain initial conditions of wealth distribution. We may then, under certain conditions,if we allow also for new entries, derive a steady state of the joint distribution