The past few decades have seen significant absolute and relative increases in numbers of urban residents. The process of city or community growth, however, has been exceedingly uneven in the sense that only a proportion of those villages and towns that stood on the threshold of urbanization and sustained population growth have emerged as cities. Some communities have experienced dramatic population increases while others have barely sustained themselves in terms of population, or at best have realized modest population gains. Finally, significant numbers of small communities have been faced with relatively large population declines.