Dynamic Array Formula in Google Sheets

I’m grappling with what should be a straightforward task in Google Sheets. In my sheet, column A lists categories (such as 1, 2, 3, etc.), and column B is intended to automatically show the most recent category from column A up to each row. While a manual copy-paste of a formula works, I’m seeking an array-based solution that populates the column seamlessly. For instance, consider this alternative approach:

=ARRAYFORMULA(OFFSET($A$1, COUNTA($A$1:INDIRECT("A" & ROW())) - 1, 0))

Any suggestions to improve this setup?

In my experience, leveraging a combination of ARRAYFORMULA and LOOKUP can streamline this process effectively. I used a formula like ARRAYFORMULA(IF(LEN(A1:A), LOOKUP(ROW(A1:A), ROW(A1:A)/(A1:A<>“”), A1:A), “”)), which dynamically tracks the latest filled cell in column A. This approach reduces reliance on volatile functions like OFFSET or INDIRECT, thereby improving performance and maintenance. Additionally, it integrates smoothly with other data, making it a versatile solution for dynamic data retrieval in Google Sheets.

hey try this: =ARRAYFORMULA(IF(A1:A<>‘’,A1:A, vlookup(row(A1:A),{filter(row(A1:A),A1:A<>‘’), filter(A1:A,A1:A<>‘’)},2,1))) . it backfills the last non empty value for you. hope it helps out!

I experimented with using a combination of INDEX and MATCH during a previous project and found it to be a robust alternative. With this approach, an array formula scans through the data sequentially and then picks out the most recent entry effectively. In my setup, doing so eliminated some of the inconsistencies I experienced with OFFSET and LOOKUP, particularly in complex sheets. It required careful calibration of the MATCH criteria, but once configured it consistently produced the desired result, even when data updates were frequent.