The following formula returns the values posted in column C:
Formula: copy to clipboard
=IF(IFERROR(AGGREGATE(14,6,ROW(B$1:B1)/(B$1:B1<=-50),1),0)>IFERROR(AGGREGATE(14,6,ROW(B$1:B1)/(B$1:B1=0),1),0),A1*10,A1)

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