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:
| Country | Contestant | Age | Height (cm) | Height (ft) | Hometown |
| --- | --- | --- | --- | --- | --- |
| Argentina | Yanina Ruiz | 24.0 | 175.0 | 5'9" | Morón |
| Bahamas | Nikie Severe | 26.0 | 170.0 | 5'7" | Freeport |
| Bolivia | Flavia Foianini | 20.0 | 176.0 | 5'9.5" | Santa Cruz |
| Brazil | Mariana Notarangelo | 23.0 | 175.0 | 5'9" | Rio de Janeiro |
| Canada | Mariana Valente | 24.0 | 175.0 | 5'9" | Toronto |
| Colombia | Alejandra Tovar | 23.0 | 170.0 | 5'7" | Neiva |
| Costa Rica | Angie Alfaro | 18.0 | 174.0 | 5'8.5" | Alajuela |
| Dominican Republic | Audris Rijo | 24.0 | 170.0 | 5'7" | Santo Domingo |
| El Salvador | Michelle Bustamante | 19.0 | 175.0 | 5'9" | La Libertad |
| Guatemala | Jessana Paté | 22.0 | 177.0 | 5'9.5" | Guatemala City |
| Honduras | Blaise Masey | 20.0 | 173.0 | 5'8" | San Pedro Sula |
| Paraguay | Viviana Benítez | 24.0 | 172.0 | 5'7.5" | San Juan Bautista |
| Peru | Danissa Zurek | 19.0 | 173.0 | 5'8" | Lima |
| Poland | Iwona Wyrzykowska | 19.0 | 171.0 | 5'7.5" | Lodz |
| Puerto Rico | Yerlyn Rodríguez | 23.0 | 178.0 | 5'10" | Mayagüez |
| Spain | Ara Jurado Calero | 21.0 | 181.0 | 6'0" | Peñarroya |
| United States | Amanda Delgado | 20.0 | 176.0 | 5'9.5" | Upland |
| Uruguay | Cinthia Furtado | 26.0 | 172.0 | 5'7.5" | Durazno |
Question:
What is the number of contestants who are aged exactly 18?
Answer:
1.0