A power query solution
let
Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
#"Changed Type" = Table.TransformColumnTypes(Source,{{"DATE", type date}}),
#"Removed Other Columns" = Table.SelectColumns(#"Changed Type",{"DATE", "POINTS"}),
#"Filtered Rows" = Table.SelectRows(#"Removed Other Columns", each [DATE] < #date(2021, 11, 8)),
#"Calculated Sum" = List.Sum(#"Filtered Rows"[POINTS])
in
#"Calculated Sum"
Power Query is a free AddIn for Excel 2010 and 2013, and is built-in functionality from Excel 2016 onwards (where it is referred to as "Get & Transform Data").
It is a powerful yet simple way of getting, changing and using data from a broad variety of sources, creating steps which may be easily repeated and refreshed. I strongly recommend learning how to use Power Query - it's among the most powerful functionalities of Excel.
- Follow this link to learn how to install Power Query in Excel 2010 / 2013.
- Follow this link for an introduction to Power Query functionality.
- Follow this link for a video which demonstrates how to use Power Query code provided.
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