| Año | Valor |
|---|---|
| 1981-01-01 | 32.690000 |
| 1982-01-01 | 32.690000 |
| 1983-01-01 | 33.740000 |
| 1984-01-01 | 32.120000 |
| 1985-01-01 | 34.020000 |
| 1986-01-01 | 32.160000 |
| 1987-01-01 | 34.210000 |
| 1988-01-01 | 37.300000 |
| 1989-01-01 | 38.360000 |
| 1990-01-01 | 39.290000 |
| 1991-01-01 | 39.460000 |
| 1992-01-01 | 39.480000 |
| 1993-01-01 | 41.950000 |
| 1994-01-01 | 45.170000 |
| 1995-01-01 | 47.210000 |
| 1996-01-01 | 48.660000 |
| 1997-01-01 | 50.130000 |
| 1998-01-01 | 52.700000 |
| 1999-01-01 | 53.570000 |
| 2000-01-01 | 54.010000 |
Fuente: World Bank