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README.md

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-# VBA-Golden-Ratio
+# VBA Golden Ratio
 Excel equidistant background coloring using the golden ratio and VBA.
+
+![Macro Output](./vba_golden_ratio_result.png)
+
+## Usage
+To use this file, call the `ColorUniqueCellsUsingGoldenRatio` subroutine with a [`Range`](https://docs.microsoft.com/en-us/office/vba/api/Excel.Range(object)) argument.
+
+```vba
+Dim selection As range
+Set selection = Application.selection
+ColorUniqueCellsUsingGoldenRatio selection ' or: Call ColorUniqueCellsUsingGoldenRatio(selection)
+```
+
+## Citations
+* https://gamedev.stackexchange.com/questions/46463/how-can-i-find-an-optimum-set-of-colors-for-10-players
+* https://stackoverflow.com/questions/3018313/algorithm-to-convert-rgb-to-hsv-and-hsv-to-rgb-in-range-0-255-for-both
+* https://www.howtobuildsoftware.com/index.php/how-do/cr3z/vba-ms-access-double-modulus-mod-with-doubles