|Rank|Nation|Gold|Silver|Bronze|Total|
|---|---|---|---|---|---|
|1|France|28|28|24|80|
|2|Romania|16|3|5|24|
|3|Canada|14|10|15|39|
|4|Quebec|8|4|16|28|
|5|Morocco|6|11|7|24|
|6|Tunisia|4|7|1|12|
|7|Egypt|2|5|4|11|
|8|Switzerland|2|1|5|8|
|9|Senegal|2|1|3|6|
|10|French Community of Belgium|1|3|6|10|
|11|Madagascar|1|2|3|6|
|12|Burkina Faso|1|-|2|3|
|13|Togo|1|-|1|2|
|14|Guinea|1|-|-|1|
|15|Lebanon|1|-|-|1|
|16|Ivory Coast|-|3|3|6|
|17|Republic of the Congo|-|3|2|5|
|18|New Brunswick|-|1|2|3|
|19|Central African Republic|-|1|-|1|
|20|Dominica|-|1|-|1|
|21|Gabon|-|1|-|1|
|22|Mali|-|1|-|1|
|23|Cambodia|-|-|2|2|
|24|Luxembourg|-|-|2|2|
|25|Mauritius|-|-|2|2|
|26|Burundi|-|-|1|1|
|27|Djibouti|-|-|1|1|
|28|Vietnam|-|-|1|1|

Question: how many counties have at least one silver medal?
Answer: 18