  
<prompt> Oke ọnwụ ụmụaka maka ụmụaka ekpughepuru n'egwu nke ọnwụ | Oke ọnwụ ụmụaka maka ụmụaka ekpughepuru n'egwu nke ọnwụ | (Nwa ọhụrụ, 1990, 21.4) (Ka amụchara nwa ọhụrụ, 1990, 12.4) (Ụmụ ntakịrị, 1990, 33.8) (Nwata, 1990, 5.1) (Erughi afọ ise, 1990, 38.8) (Nwa ọhụrụ, 1997, 19) (Ka amụchara nwa ọhụrụ, 1997, 9.6) (Ụmụ ntakịrị, 1997, 28.5) (Nwata, 1997, 5.9) (Erughi afọ ise, 1997, 34.2) (Nwa ọhụrụ, 2002, 15.5) (Ka amụchara nwa ọhụrụ, 2002, 6.6) (Ụmụ ntakịrị, 2002, 22.1) (Nwata, 2002, 5) (Erughi afọ ise, 2002, 27) (Nwa ọhụrụ, 2007, 13.6) (Ka amụchara nwa ọhụrụ, 2007, 5.7) (Ụmụ ntakịrị, 2007, 19.3) (Nwata, 2007, 2) (Erughi afọ ise, 2007, 21.3) (Nwa ọhụrụ, 2009, 15.4) (Ka amụchara nwa ọhụrụ, 2009, 7.7) (Ụmụ ntakịrị, 2009, 23.1) (Nwata, 2009, 5.1) (Erughi afọ ise, 2009, 28.1) (Nwa ọhụrụ, 2012, 13.7) (Ka amụchara nwa ọhụrụ, 2012, 3.5) (Ụmụ ntakịrị, 2012, 17.2) (Nwata, 2012, 3.8) (Erughi afọ ise, 2012, 21) <response> Oke ọnwụ ụmụaka gbadara n'ofe afọ gara aga, site na ọnwụ ụmụaka abụọ n'ime ụzọ atọ nke ụmụaka ndị mụrụ n'egwu nke ọnwụ na 1990 ruo ọnwụ ụmụaka 3.8 kwa ụmụaka abụọ n'ime ụzọ atọ nke ụmụaka ndị mụrụ n'egwu nke ọnwụ na 2012.  