Database: world_development_indicators
Question: 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.
SQL: 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 )