London (CNN Business) Renault turned in its worst financial performance in a decade in 2019 as plunging margins in its core business and a dramatic slump in contributions from alliance partner Nissan wiped out its earnings.

The French carmaker said Friday that net profit dropped 99% last year to just €19 million ($21 million) from €3.5 billion ($3.8 billion) in 2018. Contributions from Nissan, in which it holds a controlling stake, slid nearly 85%.

Renault RNLSY and Nissan have been rocked by fallout from the scandal involving their former chairman Carlos Ghosn. He spent most of last year in Japan awaiting trial on charges of financial misconduct before jumping bail and fleeing to Lebanon in December.

Ghosn's departure from the alliance has strained ties between the carmakers, and led to turmoil at the top of Renault, where he was also CEO. The company's next chief executive, Luca de Meo , will take the reins in July following the dismissal of Ghosn's immediate successor, Thierry Bollore.

Tensions within the alliance have coincided with an extended sales slump in China that threatens to keep the global car industry in recession for a third consecutive year in 2020. The coronavirus outbreak in the world's largest car market will only make things worse.

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