Partial own subsidiary to associate due to subsi issued new shares

Dear Sir,

would be appreciate if you could advise the accounting treatment for the dilution of shareholding percentage in partially owned subsidiary.

For exam, Company A (Parent) has 51% shareholding in Company B (partially owned subsidiary of Company A) as at 31 December 2018.

In year 2019, Company B (Subsidiary) allotted shares to 2 new shareholders then the Company A’s (Parent) shareholding in Company B(Subsidiary) reduced from 51% to 40%.

In this case, may I know how should we account for the change of shareholding in subsidiary in the book of Company.

Thank you.

Best Regards,
MMnoe