| Año | Valor |
|---|---|
| 1960-01-01 | 0.000073 |
| 1961-01-01 | 0.000078 |
| 1962-01-01 | 0.000081 |
| 1963-01-01 | 0.000082 |
| 1964-01-01 | 0.000089 |
| 1965-01-01 | 0.000094 |
| 1966-01-01 | 0.000097 |
| 1967-01-01 | 0.000103 |
| 1968-01-01 | 0.000108 |
| 1969-01-01 | 0.000112 |
| 1970-01-01 | 0.000116 |
| 1971-01-01 | 0.000119 |
| 1972-01-01 | 0.000142 |
| 1973-01-01 | 0.000202 |
| 1974-01-01 | 0.000327 |
| 1975-01-01 | 0.000349 |
| 1976-01-01 | 0.000379 |
| 1977-01-01 | 0.000427 |
| 1978-01-01 | 0.000487 |
| 1979-01-01 | 0.000583 |
Fuente: World Bank