What is the description of the type of the company who concluded its contracts most recently?
CREATE TABLE Maintenance_Contracts (maintenance_contract_company_id VARCHAR, contract_end_date VARCHAR); CREATE TABLE Third_Party_Companies (company_name VARCHAR, company_id VARCHAR, company_type_code VARCHAR); CREATE TABLE Ref_Company_Types (company_type_code VARCHAR)
[SQL] SELECT T1.company_name FROM Third_Party_Companies AS T1 JOIN Maintenance_Contracts AS T2 ON T1.company_id = T2.maintenance_contract_company_id JOIN Ref_Company_Types AS T3 ON T1.company_type_code = T3.company_type_code ORDER BY T2.contract_end_date DESC LIMIT 1 [/SQL]