| Año | Valor |
|---|---|
| 1961-01-01 | 7.640967 |
| 1962-01-01 | 4.969791 |
| 1963-01-01 | 28.522572 |
| 1964-01-01 | 17.061003 |
| 1965-01-01 | 4.315197 |
| 1966-01-01 | 8.914573 |
| 1967-01-01 | 4.221194 |
| 1968-01-01 | 12.581006 |
| 1969-01-01 | 6.809917 |
| 1970-01-01 | 11.415032 |
| 1971-01-01 | 6.544010 |
| 1972-01-01 | 22.481959 |
| 1973-01-01 | 38.135921 |
| 1974-01-01 | 43.627840 |
| 1975-01-01 | 21.873738 |
| 1976-01-01 | 27.593191 |
| 1977-01-01 | 28.086847 |
| 1978-01-01 | 21.607491 |
| 1979-01-01 | 21.473113 |
| 1980-01-01 | 17.335386 |
Fuente: World Bank