Excel drop-down menu
When you have selected a good cell, click Data---validity. This time the Effectivity setting option is entered. In the Settings tab, select the validity condition as a sequence, tick the drop-down arrow, and enter the contents of the menu inside the source, separated by commas.
When you set the source, you can also click to set the selection range, such as: = $G $13: $G $. Of course, if we were in $g$13: $G, we entered the contents of the sequence.
Sum to previous column
=sum (INDIRECT ("R1c:r[-1]c",))
where R stands for rows, c for columns, [] for offsets, no square brackets for absolute address references
For example, R1C1 indicates that the first row of the first column crosses where the a1,r[1]c[1] represents a column and a row relative to the current cell, like the lower right offset
The indirect function in Excel returns and displays the contents of the specified reference. Use the indirect function to refer to the names of other workbooks, worksheet names, and cell references.
This article from "Do not accumulate kuibu, not even thousands of Miles" blog, please be sure to keep this source http://wangzhichao.blog.51cto.com/2643325/1734804
Excel using tips to collect