| 年份 | 尼日利亚 |
|---|---|
| 2023 | - |
| 2022 | - |
| 2021 | 13.083 |
| 2020 | 12.997 |
| 2019 | 12.989 |
| 2018 | 13.239 |
| 2017 | 13.435 |
| 2016 | 13.638 |
| 2015 | 13.803 |
| 2014 | 13.892 |
| 2013 | 14.004 |
| 2012 | 14.193 |
| 2011 | 14.336 |
| 2010 | 14.628 |
| 2009 | 14.82 |
| 2008 | 15.161 |
| 2007 | 15.322 |
| 2006 | 15.561 |
| 2005 | 15.883 |
| 2004 | 16.271 |
| 2003 | 16.541 |
| 2002 | 16.919 |
| 2001 | 17.158 |
| 2000 | 17.464 |
| 1999 | 17.865 |
| 1998 | 18.289 |
| 1997 | 18.531 |
| 1996 | 18.757 |
| 1995 | 18.859 |
| 1994 | 18.87 |
| 1993 | 18.702 |
| 1992 | 18.805 |
| 1991 | 18.819 |
| 1990 | 18.631 |
| 1989 | 18.58 |
| 1988 | 18.694 |
| 1987 | 18.807 |
| 1986 | 18.928 |
| 1985 | 18.795 |
| 1984 | 18.739 |
| 1983 | 18.759 |
| 1982 | 18.896 |
| 1981 | 18.982 |
| 1980 | 19.17 |
| 1979 | 19.343 |
| 1978 | 19.539 |
| 1977 | 19.886 |
| 1976 | 20.49 |
| 1975 | 21.269 |
| 1974 | 21.906 |
| 1973 | 22.485 |
| 1972 | 23.071 |
| 1971 | 23.708 |
| 1970 | 24.347 |
| 1969 | 25.152 |
| 1968 | 25.356 |
| 1967 | 26.201 |
| 1966 | 25.111 |
| 1965 | 25.207 |
| 1964 | 25.42 |
| 1963 | 25.594 |
| 1962 | 25.92 |
| 1961 | 25.999 |
| 1960 | 26.235 |