Hi,

B1:
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=SUMIFS($C$8:$C$23,$B$8:$B$23,">="&TODAY()-30)


B2:
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=SUMIFS($C$8:$C$23,$B$8:$B$23,">="&TODAY()-60)-B1


B3:
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=SUMIFS($C$8:$C$23,$B$8:$B$23,">="&TODAY()-90)-SUM(B1:B2)


B4:
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=SUMIFS($C$8:$C$23,$B$8:$B$23,"<"&TODAY()-90)