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Since we're dealing with a "=DATE" range, I'll stick to that specific idiom.
When dates are processed thru Excel, there are characters used as "identity" holders, but ignored while dates are processed. The information in cell [A1] would be identical (to the DATE feature) as information in cell [$A$1].
If you use this data block example in a blank spreadsheet, when you begin stepping into the error code, you will see the references to [$A$1] while the code references [A1].
Since the date entry format is [Year, Month, Day], this code simply looks in Cells N3,O11 and P3 to collect it's data.
While you can associate $ characters in many excel equations, using them in the DATE routine is simply another way to express one cell in two formats.
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