This document discusses how to sum cells in Excel based on their background color. It provides two methods:
1. Using the SUMIF formula and manually typing in the background colors. This is cumbersome for large lists.
2. Using a user-defined function (UDF) called ColorIndex that returns the color index of a cell. This simplifies using SUMIF.
A better approach uses an improved UDF called SumByColor that directly sums the values in a range that match the background color of a reference cell. Users enter the SumByColor function with the reference cell and range to quickly sum cells by color.