1863 . . . 15 468,513 164,500 1866 ... 16 918,857 478,176 1869 . . . 21 1 , 519 , 149 992,715 1872 . . . 30 4 , 056 , 592 1 , 857.249 1875 . . . 34 5 , 912 , 813 2 , 692 , 380 1876 . . . 387