| Año | Valor |
|---|---|
| 1970-01-01 | 3.022500 |
| 1971-01-01 | 3.770200 |
| 1972-01-01 | 4.495400 |
| 1973-01-01 | 4.185400 |
| 1974-01-01 | 3.985000 |
| 1975-01-01 | 4.532900 |
| 1976-01-01 | 5.122100 |
| 1977-01-01 | 4.920400 |
| 1978-01-01 | 5.607400 |
| 1979-01-01 | 4.989500 |
| 1980-01-01 | 4.976800 |
| 1981-01-01 | 5.296400 |
| 1982-01-01 | 5.519100 |
| 1983-01-01 | 5.683400 |
| 1984-01-01 | 5.193200 |
| 1985-01-01 | 5.114700 |
| 1986-01-01 | 4.765200 |
| 1987-01-01 | 4.948700 |
| 1988-01-01 | 5.359000 |
| 1989-01-01 | 6.170300 |
Fuente: World Bank