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:
| Winner | Country | Winter Olympics | FIS Nordic World Ski Championships | Holmenkollen |
| --- | --- | --- | --- | --- |
| Hallgeir Brenden | Norway | 1956.0 | 1956.0 | 1956 |
| Eero Mäntyranta | Finland | 1964.0 | 1964.0 | 1962, 1964, 1968 |
| Harald Grønningen | Norway | 1968.0 | 1968.0 | 1960, 1961 |
| Thomas Wassberg | Sweden | 1980.0 | 1980.0 | 1979, 1985 |
| Gunde Svan | Sweden | 1984.0 | 1989.0 | 1985 |
Question:
What is the FIS Nordic World Ski Championship years when the winter Olympics took place in 1968?
Answer:
1968.0