Placing the average term at five years, then, and the average mortality at twenty per cent, there would be in service at any given time some 6,000 men and women. In fact, Sir William Berkeley, in his famous report of 1671, estimated the number of servants in the colony at this figure.[3-7] On the other hand an annual accession of 1125 to the class of freedmen would in five years amount to 5,625, in ten years to 11,250, in fifteen to 16,875, in twenty to 22,500. At the end of half a century no less than 56,250 persons would have emerged from servitude to become free citizens. Although there is every reason to believe that these figures are substantially correct,[3-8] their accuracy or lack of accuracy in no way affect the principle involved. From its very nature it was impossible that the system of indentured servants should long remain the chief factor in the industrial life of the colony or supply most of the labor. It is true, of course, that the number of those completing their terms of indenture is not an absolute gauge, at any given date, of the size of the freedman class. To determine this it would be necessary to know the average span of life of the freedman, a thing certainly not worked out at the time and impossible of accomplishment now. We may assume, however, that it was relatively long. The newcomer who had lived through the first terrible year in the tobacco fields had been thoroughly tested, "seasoned" as the planters called it, and was reasonably certain of reaching a mature age. Moreover, the servants were almost universally of very tender years. Seldom indeed would a dealer accept one over twenty-eight, and the average seems to have been between seventeen and twenty-three. The reasons for this are obvious. Not only were young men and women more adaptable to changed conditions, more capable of resisting the Virginia climate, stronger and more vigorous, but they proved more tractable and entered upon the adventure more eagerly.[3-9] These conclusions are fully borne out by an examination of the lists of servants given in Hotten's _Emigrants to America_. Of the first 159 servants here entered whose ages are attached, the average is twenty-three years.[3-10] And as many of these persons were brought over as skilled artisans to take part in the industrial life which the Company had planned for the colony, it is probable that they were much older than the average servant of later days who came as an agricultural laborer. There is every reason to believe, then, that the average servant was still in his prime when he completed his term, perhaps not more than twenty-six or twenty-seven, with many years of usefulness and vigor before him.