| Año | Valor |
|---|---|
| 1961-01-01 | 18.089758 |
| 1962-01-01 | 13.973884 |
| 1963-01-01 | 19.972640 |
| 1964-01-01 | 21.550741 |
| 1965-01-01 | 16.674484 |
| 1966-01-01 | 25.949749 |
| 1967-01-01 | 7.125758 |
| 1968-01-01 | 12.662942 |
| 1969-01-01 | 10.221488 |
| 1970-01-01 | 14.762162 |
| 1971-01-01 | 18.058750 |
| 1972-01-01 | 25.926418 |
| 1973-01-01 | 32.749710 |
| 1974-01-01 | 44.313788 |
| 1975-01-01 | 23.228115 |
| 1976-01-01 | 47.474943 |
| 1977-01-01 | 29.411765 |
| 1978-01-01 | 12.999610 |
| 1979-01-01 | 14.849906 |
| 1980-01-01 | 39.039041 |
Fuente: World Bank