| Año | Valor |
|---|---|
| 1976-01-01 | 21.074099 |
| 1977-01-01 | 20.890599 |
| 1978-01-01 | 18.287244 |
| 1979-01-01 | 16.050955 |
| 1980-01-01 | 21.276596 |
| 1981-01-01 | 15.634772 |
| 1982-01-01 | 18.042400 |
| 1983-01-01 | 8.176615 |
| 1984-01-01 | 11.834320 |
| 1985-01-01 | 12.190167 |
| 1986-01-01 | 10.821806 |
| 1987-01-01 | 20.762398 |
| 1988-01-01 | 21.703297 |
| 1989-01-01 | 19.751844 |
| 1990-01-01 | 19.285254 |
| 1991-01-01 | 20.115681 |
| 1992-01-01 | 21.800643 |
| 1993-01-01 | 21.572894 |
| 1994-01-01 | 20.177778 |
| 1995-01-01 | 13.735009 |
Fuente: World Bank