The Common Locale Data Repository (CLDR) Project is a project of the Unicode Consortium to provide extensive locale data. CLDR contains locale-specific information that an operating system will typically provide to applications. This information includes number formats, date, time and currency strings, character classification (lower, upper, printable, and the like), string collation rules and others. For more information, see Behavior Affected by Locales.
All Oracle Solaris 11.4 locale data is aligned to the CLDR data version 28. Some locales are not aligned to the CLDR data for compatibility with previous Oracle Solaris releases. The UTF-8 and non-UTF-8 forms of the ja_JP, ko_KR, th_TH, zh_CN, zh_HK, and zh_TW locales are not aligned. These locales are based on other sources and do not use the CLDR data. There is a CLDR-based variant of Japanese UTF-8 available under the name ja_JP.UTF-8@cldr.
For more details on CLDR, refer to ICU-TC Home Page.