This is the 2251st most frequent Polish word.
spadły
"Spadły" means "they fell" or "have fallen" in English.
Here, "spadły" is used as the past tense of the verb "spaść," describing an action that the apples performed themselves.
Jabłka spadły z drzewa.
The apples fell from the tree.
In this case, "spadły" refers to the decrease of prices, using the verb "spaść" in an abstract context.
Ceny mieszkań spadły w ostatnim roku.
Apartment prices fell in the last year.
"Spadły" here again means 'fell' or 'dropped,' applying to temperatures as the subject of the action.