the world's (1).... growth rate rose from about 1.5 percent per year from 1950 to 1951 to a peak of over 2 percent in the early 1960s due to reduction in mortality. growth rates there after started to (2).... due to rising age at marriage as well as increasing availability and use of effective contraceptive methods. note that changes in population growth have not always been (3)...A dip in the growth rate from 1959 to 1960, for (4)...,was due to the Great Leap Forward in China . During that time, both natural disasters(5)....decreased agricultural output in the wake of massive social reorganization caused China's death rate to rise sharply and its fertility rate to fall by almost half.