Symfony PHP - folder order

OVERVIEW The site stores all client information and files for each client. These are all stored according to year, with set folders in each year. Each client has the following sections - Taxation, Documentation, Correspondance - and relevant documents are stored in those sections. Each new year, a folder is created for that new year and the set folders are automatically created - see screenshot of the folders in the Taxation section. The automatically created folders only started in 2015, but some clients have files that need to be uploaded from earlier years. The system allows us to manually create these earlier years e.g 2014, but this folder is appearing above the 2019 folder, instead of at the bottom of the page, under the 2015 folder. REQUIREMENTS FOR THIS PROJECT I need you to ensure that folders for earlier years are created underneath the 2015 folder ie. the folders must start with 2019 and go down the page in sequential order according to year