| Año | Valor |
|---|---|
| 1960-01-01 | 9.700826 |
| 1961-01-01 | 10.531609 |
| 1962-01-01 | 10.978036 |
| 1963-01-01 | 12.231520 |
| 1964-01-01 | 13.195111 |
| 1965-01-01 | 13.857939 |
| 1966-01-01 | 15.763522 |
| 1967-01-01 | 14.951554 |
| 1968-01-01 | 14.840071 |
| 1969-01-01 | 15.095074 |
| 1970-01-01 | 15.835127 |
| 1971-01-01 | 17.353258 |
| 1972-01-01 | 17.011364 |
| 1973-01-01 | 14.940646 |
| 1974-01-01 | 12.965783 |
| 1975-01-01 | 13.954653 |
| 1976-01-01 | 18.114219 |
| 1977-01-01 | 19.843298 |
| 1978-01-01 | 19.256004 |
| 1979-01-01 | 18.436204 |
Fuente: World Bank