Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Reserve | District | IUCN | Est. | Description |
| --- | --- | --- | --- | --- |
| Aguacaliente | Toledo | IV | 1998.0 | Terrestrial. |
| Cockscomb Basin | Stann Creek / Toledo | IV | 1997.0 | Terrestrial. |
| Corozal Bay | Belize / Corozal | IV | 1998.0 | Marine. |
| Crooked Tree | Belize / Orange Walk | IV | 1984.0 | Ramsar site . Boundaries ill defined. Terrestrial. |
| Gales Point | Belize | IV | 1998.0 | Terrestrial. |
| Spanish Creek | Belize / Orange Walk | IV | 2002.0 | Terrestrial. |
| Swallow Caye | Belize | IV | 2002.0 | Marine. |
Question:
What is the IUCN for the Cockscomb Basin reserve when the Est. is less than 1998?
Answer:
IV