| Año | Valor |
|---|---|
| 1970-01-01 | 0.414650 |
| 1971-01-01 | 0.665714 |
| 1972-01-01 | 0.571150 |
| 1973-01-01 | 1.030960 |
| 1974-01-01 | 3.522580 |
| 1975-01-01 | 2.991411 |
| 1976-01-01 | 2.870797 |
| 1977-01-01 | 1.700144 |
| 1978-01-01 | 1.974642 |
| 1979-01-01 | 4.449386 |
| 1980-01-01 | 5.447512 |
| 1981-01-01 | 2.841288 |
| 1982-01-01 | 1.949751 |
| 1983-01-01 | 2.519046 |
| 1984-01-01 | 2.284818 |
| 1985-01-01 | 2.147697 |
| 1986-01-01 | 1.133821 |
| 1987-01-01 | 1.980319 |
| 1988-01-01 | 1.456433 |
| 1989-01-01 | 2.140903 |
Fuente: World Bank