diff --git a/src/NodaTimeAutotranslater.php b/src/NodaTimeAutotranslater.php
index 0ded8b8..11ac318 100644
--- a/src/NodaTimeAutotranslater.php
+++ b/src/NodaTimeAutotranslater.php
@@ -14,198 +14,6 @@ final class NodaTimeAutotranslater {
 
     // TODO: Move these to NodaTimeAutotranslaterLocales
 
-    const LANGS_SINCE_START_FORMAT_YEAR = [
-        'ar' => '%s-',
-        'de' => 'Seit %s',
-        'en' => 'Since %s',
-        'es' => 'Desde %s',
-        'fa' => '%s-',
-        'fr' => 'Depuis %s',
-        'hu' => '%s-től',
-        'id' => 'Sejak %s',
-        'it' => 'Dal %s',
-        'ka' => '%s წლიდან',
-        'ko' => '%s부터',
-        'pl' => 'Od %s r.',
-        'pt' => '%s dC',
-        'ro' => 'Din %s',
-        'ru' => 'С %s г.',
-        'ta' => '%s  முதல்',
-        'tl' => 'Mula noong %s',
-        'tr' => '%s-',
-
-        // Languages that don't really need a specific locale
-        'ja' => '%s以来',
-        'zh' => '自%s以來',
-    ];
-
-    const LANGS_AFTER_START_FORMAT_YEAR = [
-        'ar' => '%s-',
-        'de' => 'Nach %s',
-        'en' => 'After %s',
-        'es' => 'Despues de %s',
-        'fa' => '%s-',
-        'fr' => 'Après %s',
-        'hu' => '%s után',
-        'id' => 'Setelah %s',
-        'it' => 'Dopo il %s',
-        'ka' => '%s წლის შემდეგ',
-        'ko' => '%s 년 이후',
-        'pl' => 'Po %s r.',
-        'pt' => 'Depois de %s',
-        'ro' => 'După %s',
-        'ru' => 'после %s г.',
-        'ta' => '%s  க்குப் பிறகு',
-        'tl' => 'Pagkaraan ng %s',
-        'tr' => '%s-',
-
-        // Languages that don't really need a specific locale
-        'ja' => '%s以降',
-        'zh' => '%s以后',
-    ];
-
-    const LANGS_UNTIL_START_FORMAT_YEAR = [
-        'ar' => '-%s',
-        'de' => 'Bis %s',
-        'en' => 'Until %s',
-        'es' => 'Hasta %s',
-        'fa' => '-%s',
-        'fr' => 'Jusqu\'en %s',
-        'hu' => '%s-ig',
-        'id' => 'Sampai %s',
-        'it' => 'Fino al %s',
-        'ka' => '%s წლამდე',
-        'ko' => '%s까지',
-        'pl' => 'do %s roku',
-        'pt' => 'até %s',
-        'ro' => 'până în %s',
-        'ru' => 'до %s г.',
-        'ta' => '%s வரை',
-        'tl' => 'Hanggang %s',
-        'tr' => '%s-',
-
-        // Languages that don't really need a specific locale
-        'ja' => '%sまで',
-        'zh' => '直到%s',
-    ];
-
-    const LANGS_BEFORE_START_FORMAT_YEAR = [
-        'ar' => '-%s',
-        'de' => 'Vor %s',
-        'en' => 'Before %s',
-        'es' => 'Antes de %s',
-        'fa' => '-%s',
-        'fr' => 'Avant %s',
-        'hu' => '%s előtt',
-        'id' => 'Sebelum %s',
-        'it' => 'Prima del %s',
-        'ka' => '%s წლამდე',
-        'ko' => '%s 년 이전',
-        'pl' => 'Przed %s',
-        'pt' => 'Antes de %s',
-        'ro' => 'înainte de %s',
-        'ru' => 'до %s г.',
-        'ta' => '%s க்கு முன்',
-        'tl' => 'Bago ang %s',
-        'tr' => '%s-',
-
-        // Languages that don't really need a specific locale
-        'ja' => '%s以前',
-        'zh' => '%s之前',
-    ];
-
-    const LANGS_CENTURY_FORMAT = [
-        'ar' => 'القرن ال %s',
-        'de' => '%s. Jahrhundert',
-        'en' => '%s. century',
-        'es' => 'Siglo %s',
-        'fa' => 'قرن %s',
-        'fr' => '%sème siècle',
-        'hu' => '%s. század',
-        'id' => 'Abad ke-%s',
-        'it' => '%sesimo secolo',
-        'ka' => 'მე -%s საუკუნე',
-        'ko' => '%s 세기',
-        'pl' => '%s wiek',
-        'pt' => 'Século %s',
-        'ro' => 'Secolul al %s-lea',
-        'ru' => '%s век',
-        'ta' => '%s ஆம் நூற்றாண்டு',
-        'tl' => 'Ika-%s na siglo',
-        'tr' => '%s. yüzyıl',
-        'ja' => '%s世紀',
-        'zh' => '%s世紀',
-    ];
-
-    const LANGS_CENTURIES_FORMAT = [
-        'ar' => 'القرن ال %s-%s',
-        'de' => '%s.-%s. Jahrhundert',
-        'en' => '%s.-%s. century',
-        'es' => 'Siglo %s-%s',
-        'fa' => 'قرن %s-%s',
-        'fr' => '%s-%sème siècle',
-        'hu' => '%s.-%s. század',
-        'id' => 'Abad ke-%s-%s',
-        'it' => '%s-%sesimo secolo',
-        'ka' => 'მე -%s-%s საუკუნე',
-        'ko' => '%s-%s 세기',
-        'pl' => '%s-%s wiek',
-        'pt' => 'Século %s-%s',
-        'ro' => 'Secolul al %s-%s-lea',
-        'ru' => '%s-%s век',
-        'ta' => '%s-%s ஆம் நூற்றாண்டு',
-        'tl' => 'Ika-%s hanggang ika-%s na siglo',
-        'tr' => '%s.-%s. yüzyıl',
-        'ja' => '%s世紀-%s世紀',
-        'zh' => '%s-%s世紀',
-    ];
-
-    const LANGS_DECADE_FORMAT = [
-        'ar' => '%s-%s',
-        'de' => '%ser Jahre',
-        'en' => '%ss',
-        'es' => '%s-%s',
-        'fa' => 'دهه %s',
-        'fr' => 'Années %s',
-        'hu' => '%s-as évek',
-        'id' => 'Tahun %s-an',
-        'it' => '%ss',
-        'ka' => '%s-იანი წლები',
-        'ko' => '%s 년대',
-        'pl' => '%s roku',
-        'pt' => 'Década de %s',
-        'ro' => 'Anii %s',
-        'ru' => '%s-е годы',
-        'ta' => '%s கள்',
-        'tl' => '%ss',
-        'tr' => '%s\'ler',
-        'ja' => '%s年代',
-        'zh' => '%s年代',
-    ];
-
-    const LANGS_DECADES_FORMAT = [
-        'ar' => '%s-%s',
-        'de' => '%s-%ser Jahre',
-        'en' => '%s-%ss',
-        'es' => '%s-%s',
-        'fa' => 'دهه %s-%s',
-        'fr' => 'Années %s-%s',
-        'hu' => '%s-%s-as évek',
-        'id' => 'Tahun %s-an sampai tahun %s-an',
-        'it' => '%s-%ss',
-        'ka' => '%s-%s-იანი წლები',
-        'ko' => '%s-%s 년대',
-        'pl' => '%s-%s roku',
-        'pt' => 'Décadas de %s-%s',
-        'ro' => 'Anii %s-%s',
-        'ru' => '%s-%s-е годы',
-        'ta' => '%s-%s கள்',
-        'tl' => '%s-%ss',
-        'tr' => '%s-%s\'ler',
-        'ja' => '%s年代から%s年代',
-        'zh' => '%s年代-%s年代',
-    ];
-
     const LANGS_SYLLABLE_CLEANING = [
         "hu" => [
             "10-as évek" => "10-es évek",
@@ -307,21 +115,21 @@ final class NodaTimeAutotranslater {
     /**
      * Applies suffix format to a time string.
      *
-     * @param string                           $tLang      Two digit ANSI language code.
+     * @param NodaTimeAutotranslaterLocales    $tLang      Two digit ANSI language code.
      * @param string                           $timeName   Time name.
      * @param NodaTimeAutotranslaterSuffixMode $suffixMode Suffix mode.
      *
      * @return string
      */
-    public static function applyBcBceFormat(string $tLang, string $timeName, NodaTimeAutotranslaterSuffixMode $suffixMode):string {
+    private static function _applyBcBceFormat(NodaTimeAutotranslaterLocales $tLang, string $timeName, NodaTimeAutotranslaterSuffixMode $suffixMode):string {
 
         switch ($suffixMode) {
         case NodaTimeAutotranslaterSuffixMode::ANY:
             return $timeName;
         case NodaTimeAutotranslaterSuffixMode::CE:
-            return \sprintf(NodaTimeAutotranslaterLocales::fromString($tLang)->eraFormatCeForSprintf(), $timeName);
+            return \sprintf($tLang->eraFormatCeForSprintf(), $timeName);
         case NodaTimeAutotranslaterSuffixMode::BCE:
-            return \sprintf(NodaTimeAutotranslaterLocales::fromString($tLang)->eraFormatBceForSprintf(), $timeName);
+            return \sprintf($tLang->eraFormatBceForSprintf(), $timeName);
         default:
             throw new Exception("Unknown case encountered for time translations.");
         }
@@ -351,6 +159,8 @@ final class NodaTimeAutotranslater {
 
         $output = [];
         $cases = NodaTimeAutotranslaterLocales::cases();
+
+        // TODO: Run gettranslations first, then loop
         foreach ($cases as $tLang) {
 
             if ($suffixMode === NodaTimeAutotranslaterSuffixMode::BCE) {
@@ -371,7 +181,7 @@ final class NodaTimeAutotranslater {
                 else $year = \sprintf($tLang->formatYearspanForSprintf(), (string)\abs($start), (string)\abs($end));
             }
 
-            $output[$tLang->name] = self::applyBcBceFormat($tLang->name, $year, $suffixMode);
+            $output[$tLang->name] = self::_applyBcBceFormat($tLang, $year, $suffixMode);
 
         }
         return $output;
@@ -446,17 +256,17 @@ final class NodaTimeAutotranslater {
 
         $output = [];
 
-        if ($start_cen === $end_cen) {
-            foreach (self::LANGS_CENTURY_FORMAT as $tLang => $format) {
-                $tLangValue = \sprintf($format, (string)\abs($start_cen));
-                $output[$tLang] = self::applyBcBceFormat($tLang, $tLangValue, $suffixMode);
+        $cases = NodaTimeAutotranslaterLocales::cases();
+        foreach ($cases as $tLang) {
+
+            if ($start_cen === $end_cen) {
+                $tLangValue = \sprintf($tLang->formatCenturyForSprintf(), (string)\abs($start_cen));
             }
-        }
-        else {
-            foreach (self::LANGS_CENTURIES_FORMAT as $tLang => $format) {
-                $tLangValue = \sprintf($format, (string)\abs($start_cen), (string)\abs($end_cen));
-                $output[$tLang] = self::applyBcBceFormat($tLang, $tLangValue, $suffixMode);
+            else {
+                $tLangValue = \sprintf($tLang->formatCenturiesForSprintf(), (string)\abs($start_cen), (string)\abs($end_cen));
             }
+            $output[$tLang->name] = self::_applyBcBceFormat($tLang, $tLangValue, $suffixMode);
+
         }
         return $output;
 
@@ -480,20 +290,21 @@ final class NodaTimeAutotranslater {
 
         $output = [];
 
-        if ($start_cen === $end_cen - 9) {
-            foreach (self::LANGS_DECADE_FORMAT as $tLang => $format) {
-                $tLangValue = \sprintf($format, (string)$start_cen, (string)$end_cen);
-                if (!empty(self::LANGS_SYLLABLE_CLEANING[$tLang])) $tLangValue = \strtr($tLangValue, self::LANGS_SYLLABLE_CLEANING[$tLang]);
-                $output[$tLang] = self::applyBcBceFormat($tLang, $tLangValue, $suffixMode);
+        $cases = NodaTimeAutotranslaterLocales::cases();
+        foreach ($cases as $tLang) {
+
+            if ($start_cen === $end_cen - 9) {
+                $tLangValue = \sprintf($tLang->formatDecadeForSprintf(), (string)$start_cen, (string)$end_cen);
+                if (!empty(self::LANGS_SYLLABLE_CLEANING[$tLang->name])) $tLangValue = \strtr($tLangValue, self::LANGS_SYLLABLE_CLEANING[$tLang->name]);
             }
-        }
-        else {
-            foreach (self::LANGS_DECADES_FORMAT as $tLang => $format) {
-                $tLangValue = \sprintf($format, (string)$start_cen, (string)($end_cen - 9));
-                if (!empty(self::LANGS_SYLLABLE_CLEANING[$tLang])) $tLangValue = \strtr($tLangValue, self::LANGS_SYLLABLE_CLEANING[$tLang]);
-                $output[$tLang] = self::applyBcBceFormat($tLang, $tLangValue, $suffixMode);
+            else {
+                $tLangValue = \sprintf($tLang->formatDecadesForSprintf(), (string)$start_cen, (string)($end_cen - 9));
+                if (!empty(self::LANGS_SYLLABLE_CLEANING[$tLang->name])) $tLangValue = \strtr($tLangValue, self::LANGS_SYLLABLE_CLEANING[$tLang->name]);
             }
+            $output[$tLang->name] = self::_applyBcBceFormat($tLang, $tLangValue, $suffixMode);
+
         }
+
         return $output;
 
     }
@@ -515,12 +326,15 @@ final class NodaTimeAutotranslater {
         $innerTimeInfo['zeit_ende'] = $timeInfo['zeit_beginn'];
         $output = [];
 
-        foreach (self::LANGS_AFTER_START_FORMAT_YEAR as $tLang => $format) {
+        $innerTls = self::getTranslations($innerTimeInfo);
 
-            $dateAlone = self::getTranslations($innerTimeInfo)[$tLang];
+        $cases = NodaTimeAutotranslaterLocales::cases();
+        foreach ($cases as $tLang) {
 
-            $timeName = \sprintf($format, $dateAlone);
-            $output[$tLang] = $timeName;
+            $dateAlone = $innerTls[$tLang->name];
+
+            $timeName = \sprintf($tLang->formatYearsAfterStartForSprintf(), $dateAlone);
+            $output[$tLang->name] = $timeName;
 
         }
         return $output;
@@ -546,12 +360,15 @@ final class NodaTimeAutotranslater {
         $innerTimeInfo['zeit_ende'] = $timeInfo['zeit_beginn'];
         $output = [];
 
-        foreach (self::LANGS_SINCE_START_FORMAT_YEAR as $tLang => $format) {
+        $innerTls = self::getTranslations($innerTimeInfo);
 
-            $dateAlone = self::getTranslations($innerTimeInfo)[$tLang];
+        $cases = NodaTimeAutotranslaterLocales::cases();
+        foreach ($cases as $tLang) {
 
-            $timeName = \sprintf($format, $dateAlone);
-            $output[$tLang] = $timeName;
+            $dateAlone = $innerTls[$tLang->name];
+
+            $timeName = \sprintf($tLang->formatYearsSinceStartForSprintf(), $dateAlone);
+            $output[$tLang->name] = $timeName;
 
         }
         return $output;
@@ -576,12 +393,17 @@ final class NodaTimeAutotranslater {
         $innerTimeInfo['zeit_beginn'] = $timeInfo['zeit_ende'];
 
         $output = [];
-        foreach (self::LANGS_BEFORE_START_FORMAT_YEAR as $tLang => $format) {
 
-            $dateAlone = self::getTranslations($innerTimeInfo)[$tLang];
+        $innerTls = self::getTranslations($innerTimeInfo);
+
+        $cases = NodaTimeAutotranslaterLocales::cases();
+        foreach ($cases as $tLang) {
+
+            $dateAlone = $innerTls[$tLang->name];
+
+            $timeName = \sprintf($tLang->formatYearsBeforeStartForSprintf(), $dateAlone);
+            $output[$tLang->name] = $timeName;
 
-            $timeName = \sprintf($format, $dateAlone);
-            $output[$tLang] = $timeName;
         }
         return $output;
 
@@ -606,12 +428,16 @@ final class NodaTimeAutotranslater {
         $innerTimeInfo['zeit_beginn'] = $timeInfo['zeit_ende'];
 
         $output = [];
-        foreach (self::LANGS_UNTIL_START_FORMAT_YEAR as $tLang => $format) {
 
-            $dateAlone = self::getTranslations($innerTimeInfo)[$tLang];
+        $innerTls = self::getTranslations($innerTimeInfo);
 
-            $timeName = \sprintf($format, $dateAlone);
-            $output[$tLang] = $timeName;
+        $cases = NodaTimeAutotranslaterLocales::cases();
+        foreach ($cases as $tLang) {
+
+            $dateAlone = $innerTls[$tLang->name];
+
+            $timeName = \sprintf($tLang->formatYearsUntilStartForSprintf(), $dateAlone);
+            $output[$tLang->name] = $timeName;
         }
         return $output;
 
@@ -743,7 +569,7 @@ final class NodaTimeAutotranslater {
             );
             if (($tLangValue = $fmt->format($dateGeneral)) === false) continue;
 
-            $output[$tLang->name] = self::applyBcBceFormat($tLang->name, $tLangValue, $suffixMode);
+            $output[$tLang->name] = self::_applyBcBceFormat($tLang, $tLangValue, $suffixMode);
 
         }
 
diff --git a/src/enums/NodaTimeAutotranslaterLocales.php b/src/enums/NodaTimeAutotranslaterLocales.php
index 8b02486..72c181f 100644
--- a/src/enums/NodaTimeAutotranslaterLocales.php
+++ b/src/enums/NodaTimeAutotranslaterLocales.php
@@ -260,6 +260,275 @@ enum NodaTimeAutotranslaterLocales {
 
     }
 
+    /**
+     * Returns the appropriate format for a timespan since a start year.
+     * Expects to be used as a format for sprintf.
+     * Example use case: Since 1921.
+     *
+     * @return string
+     */
+    public function formatYearsSinceStartForSprintf():string {
+
+        return match($this) {
+            self::ar => '%s-',
+            self::de => 'Seit %s',
+            self::en => 'Since %s',
+            self::es => 'Desde %s',
+            self::fa => '%s-',
+            self::fr => 'Depuis %s',
+            self::hu => '%s-től',
+            self::id => 'Sejak %s',
+            self::it => 'Dal %s',
+            self::ka => '%s წლიდან',
+            self::ko => '%s부터',
+            self::pl => 'Od %s r.',
+            self::pt => '%s dC',
+            self::ro => 'Din %s',
+            self::ru => 'С %s г.',
+            self::ta => '%s  முதல்',
+            self::tl => 'Mula noong %s',
+            self::tr => '%s-',
+
+            self::ja => '%s以来',
+            self::zh => '自%s以來',
+        };
+
+    }
+
+    /**
+     * Returns the appropriate format for a timespan after a start year.
+     * Expects to be used as a format for sprintf.
+     * Example use case: After 1921.
+     *
+     * @return string
+     */
+    public function formatYearsAfterStartForSprintf():string {
+
+        return match($this) {
+            self::ar => '%s-',
+            self::de => 'Nach %s',
+            self::en => 'After %s',
+            self::es => 'Despues de %s',
+            self::fa => '%s-',
+            self::fr => 'Après %s',
+            self::hu => '%s után',
+            self::id => 'Setelah %s',
+            self::it => 'Dopo il %s',
+            self::ka => '%s წლის შემდეგ',
+            self::ko => '%s 년 이후',
+            self::pl => 'Po %s r.',
+            self::pt => 'Depois de %s',
+            self::ro => 'După %s',
+            self::ru => 'после %s г.',
+            self::ta => '%s  க்குப் பிறகு',
+            self::tl => 'Pagkaraan ng %s',
+            self::tr => '%s-',
+            self::ja => '%s以降',
+            self::zh => '%s以后',
+        };
+
+    }
+
+    /**
+     * Returns the appropriate format for a timespan until an end year.
+     * Expects to be used as a format for sprintf.
+     * Example use case: Until 1921.
+     *
+     * @return string
+     */
+    public function formatYearsUntilStartForSprintf():string {
+
+        return match($this) {
+            self::ar => '-%s',
+            self::de => 'Bis %s',
+            self::en => 'Until %s',
+            self::es => 'Hasta %s',
+            self::fa => '-%s',
+            self::fr => 'Jusqu\'en %s',
+            self::hu => '%s-ig',
+            self::id => 'Sampai %s',
+            self::it => 'Fino al %s',
+            self::ka => '%s წლამდე',
+            self::ko => '%s까지',
+            self::pl => 'do %s roku',
+            self::pt => 'até %s',
+            self::ro => 'până în %s',
+            self::ru => 'до %s г.',
+            self::ta => '%s வரை',
+            self::tl => 'Hanggang %s',
+            self::tr => '%s-',
+            self::ja => '%sまで',
+            self::zh => '直到%s',
+        };
+
+    }
+
+    /**
+     * Returns the appropriate format for a century name.
+     * Example use case: 19th century.
+     *
+     * @return string
+     */
+    public function formatCenturyForSprintf():string {
+
+        return match($this) {
+            self::ar => 'القرن ال %s',
+            self::de => '%s. Jahrhundert',
+            self::en => '%s. century',
+            self::es => 'Siglo %s',
+            self::fa => 'قرن %s',
+            self::fr => '%sème siècle',
+            self::hu => '%s. század',
+            self::id => 'Abad ke-%s',
+            self::it => '%sesimo secolo',
+            self::ka => 'მე -%s საუკუნე',
+            self::ko => '%s 세기',
+            self::pl => '%s wiek',
+            self::pt => 'Século %s',
+            self::ro => 'Secolul al %s-lea',
+            self::ru => '%s век',
+            self::ta => '%s ஆம் நூற்றாண்டு',
+            self::tl => 'Ika-%s na siglo',
+            self::tr => '%s. yüzyıl',
+            self::ja => '%s世紀',
+            self::zh => '%s世紀',
+        };
+
+    }
+
+    /**
+     * Returns the appropriate format for a name spanning multiple centuries.
+     * Example use case: 19th-20th centuries.
+     *
+     * @return string
+     */
+    public function formatCenturiesForSprintf():string {
+
+        return match($this) {
+            self::ar => 'القرن ال %s-%s',
+            self::de => '%s.-%s. Jahrhundert',
+            self::en => '%s.-%s. century',
+            self::es => 'Siglo %s-%s',
+            self::fa => 'قرن %s-%s',
+            self::fr => '%s-%sème siècle',
+            self::hu => '%s.-%s. század',
+            self::id => 'Abad ke-%s-%s',
+            self::it => '%s-%sesimo secolo',
+            self::ka => 'მე -%s-%s საუკუნე',
+            self::ko => '%s-%s 세기',
+            self::pl => '%s-%s wiek',
+            self::pt => 'Século %s-%s',
+            self::ro => 'Secolul al %s-%s-lea',
+            self::ru => '%s-%s век',
+            self::ta => '%s-%s ஆம் நூற்றாண்டு',
+            self::tl => 'Ika-%s hanggang ika-%s na siglo',
+            self::tr => '%s.-%s. yüzyıl',
+            self::ja => '%s世紀-%s世紀',
+            self::zh => '%s-%s世紀',
+        };
+
+    }
+
+    /**
+     * Returns the appropriate format for a name spanning a single decade.
+     * Example use case: 1920s.
+     *
+     * @return string
+     */
+    public function formatDecadeForSprintf():string {
+
+        return match($this) {
+            self::ar => '%s-%s',
+            self::de => '%ser Jahre',
+            self::en => '%ss',
+            self::es => '%s-%s',
+            self::fa => 'دهه %s',
+            self::fr => 'Années %s',
+            self::hu => '%s-as évek',
+            self::id => 'Tahun %s-an',
+            self::it => '%ss',
+            self::ka => '%s-იანი წლები',
+            self::ko => '%s 년대',
+            self::pl => '%s roku',
+            self::pt => 'Década de %s',
+            self::ro => 'Anii %s',
+            self::ru => '%s-е годы',
+            self::ta => '%s கள்',
+            self::tl => '%ss',
+            self::tr => '%s\'ler',
+            self::ja => '%s年代',
+            self::zh => '%s年代',
+        };
+
+    }
+
+    /**
+     * Returns the appropriate format for a name spanning a some decades.
+     * Example use case: 1920s-1930s.
+     *
+     * @return string
+     */
+    public function formatDecadesForSprintf():string {
+
+        return match($this) {
+            self::ar => '%s-%s',
+            self::de => '%s-%ser Jahre',
+            self::en => '%s-%ss',
+            self::es => '%s-%s',
+            self::fa => 'دهه %s-%s',
+            self::fr => 'Années %s-%s',
+            self::hu => '%s-%s-as évek',
+            self::id => 'Tahun %s-an sampai tahun %s-an',
+            self::it => '%s-%ss',
+            self::ka => '%s-%s-იანი წლები',
+            self::ko => '%s-%s 년대',
+            self::pl => '%s-%s roku',
+            self::pt => 'Décadas de %s-%s',
+            self::ro => 'Anii %s-%s',
+            self::ru => '%s-%s-е годы',
+            self::ta => '%s-%s கள்',
+            self::tl => '%s-%ss',
+            self::tr => '%s-%s\'ler',
+            self::ja => '%s年代から%s年代',
+            self::zh => '%s年代-%s年代',
+        };
+
+    }
+
+    /**
+     * Returns the appropriate format for a timespan before an end year.
+     * Expects to be used as a format for sprintf.
+     * Example use case: Before 1921.
+     *
+     * @return string
+     */
+    public function formatYearsBeforeStartForSprintf():string {
+
+        return match($this) {
+            self::ar => '-%s',
+            self::de => 'Vor %s',
+            self::en => 'Before %s',
+            self::es => 'Antes de %s',
+            self::fa => '-%s',
+            self::fr => 'Avant %s',
+            self::hu => '%s előtt',
+            self::id => 'Sebelum %s',
+            self::it => 'Prima del %s',
+            self::ka => '%s წლამდე',
+            self::ko => '%s 년 이전',
+            self::pl => 'Przed %s',
+            self::pt => 'Antes de %s',
+            self::ro => 'înainte de %s',
+            self::ru => 'до %s г.',
+            self::ta => '%s க்கு முன்',
+            self::tl => 'Bago ang %s',
+            self::tr => '%s-',
+            self::ja => '%s以前',
+            self::zh => '%s之前',
+        };
+
+    }
+
     /**
      * Returns the appropriate format for formatting a full date (Y-m-d) in a given language
      * using strftime.