Write SQL query to solve given problem: List out the country name of upper middle income group. Which country has the earliest national account base year? List out the region where this country locates.. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT DISTINCT T1.CountryName FROM indicators AS T1 INNER JOIN country AS T2 ON T1.CountryCode = T2.CountryCode WHERE T2.IncomeGroup = 'Upper middle income' UNION SELECT longname FROM ( SELECT longname FROM country WHERE NationalAccountsBaseYear <> '' ORDER BY NationalAccountsBaseYear ASC LIMIT 1 )