| Año | Valor |
|---|---|
| 1970-01-01 | 5.433500 |
| 1971-01-01 | 5.616700 |
| 1972-01-01 | 5.828100 |
| 1973-01-01 | 5.947800 |
| 1974-01-01 | 6.603800 |
| 1975-01-01 | 6.941200 |
| 1976-01-01 | 7.333200 |
| 1977-01-01 | 7.759900 |
| 1978-01-01 | 8.821200 |
| 1979-01-01 | 9.424900 |
| 1980-01-01 | 9.831100 |
| 1981-01-01 | 9.455600 |
| 1982-01-01 | 9.429500 |
| 1983-01-01 | 10.769500 |
| 1984-01-01 | 10.245100 |
| 1985-01-01 | 10.857700 |
| 1986-01-01 | 9.784600 |
| 1987-01-01 | 10.243200 |
| 1988-01-01 | 10.515300 |
| 1989-01-01 | 10.676400 |
Fuente: World Bank