  
<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> Ụmụaka ndị nọ na di ugbu a na ebido na ọnwụ ụmụaka na 1990 ruo 1997, site na ọnwụ 5.6 kwa ọmụmụ nwa ikpeazụ ruo ọnwụ 3.7 kwa ọmụmụ nwa ikpeazụ.  