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:
| Ship name | Year | Length | Width | Passengers | Vessels | Speed |
| --- | --- | --- | --- | --- | --- | --- |
| Mytilene | 1973.0 | 138,3 m | 22,4 m | 1.73 | 225.0 | 20.0 |
| European Express | 1974.0 | 159,5 m | 21,5 m | 1.0 | 350.0 | 23.0 |
| Ionian Sky | 1974.0 | 164 m | 24 m | 1.09 | 600.0 | 22.0 |
| Theofilos | 1975.0 | 149,4 m | 23,5 m | 1.66 | 433.0 | 18.0 |
| Taxiarchis | 1976.0 | 135,8 m | 20,6 m | 591.0 | 392.0 | 18.0 |
| Aqua Jewel | 2002.0 | 108 m | 16,6 m | 1.675 | 175.0 | 18.5 |
| Aqua Maria | 1975.0 | 101,3 m | 18 m | 592.0 | 230.0 | 17.0 |
| Aqua Spirit | 2000.0 | 75 m | 15 m | 400.0 | 60.0 | 17.0 |
Question:
How many vessels are named aqua jewel?
Answer:
1.0