This property defines the Unicodes which have numeric value as 18
Characters like ᛯ,⑱,⒅, etc. are listed under 18 Numeric Value.
8 Characters are present in 18 Numeric Value starting with the Unicode point U+16EF that represents the character ᛯ.
Currently, as per latest version 15.0.0, Unicode supports 150 number of Numeric Value. Here are a few examples - 0,1,1/10, etc.