景けい気き停てい滞たい

不況 is a more common and general term for 'recession' or 'depression', while 景気停滞 specifically emphasizes the stagnation or sluggishness of the economy.

景気後退 means 'economic downturn' or 'recession', often implying a decline, whereas 景気停滞 focuses on a lack of growth or standstill.