Sorry, read a little more into your question

Have one X1 = the date of your worksheet
Have x2 =EOMONTH(F273,-3)+1 (this is 3 mths prior period start)

Then enter the array as this

=SUM(($b$2:$T$200)*($a$2:$a$200<=x1)*($a$2:$a$200 =x2))

a2:a200 are the dates
b2:b200 are the values


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macroll
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