public static function getKeyvaluesByKeyType($keyType)
    {
        if (empty($keyType)) {
            // return empty array
            return [];
        }

        $tableCache = static::tableToArray();

        // Read through the entire table cache looking for keys that match
        // the keyType
        $result = [];
        foreach ($tableCache as $key => $value) {
            list($storedType, $storedValue) = explode('__', $key, 2);
            if ($storedType == $keyType) {
                $result[$value->keyvalue] = $value;
            }
        }

        return $result;
    }