I have a selection of vehicles that have the below formula which will insert the red symbol if they are listed in the corresponding column:
=IF([日付 Date]@row < TODAY(), "Gray", IF(CONTAINS("4号室 Room 4", [問題報告RV東照明 Reporting Issue RVE Lighting]:[問題報告RV東照明 Reporting Issue RVE Lighting]), "Red"))
What I need to know is how to ensure that once the row is no longer 'todays' entry, the symbol needs to remain but turn gray (to show a history of what specific vehicles had been labeled Red). Currently, every column for every vehicle turns gray once it is no longer today, even if the [問題報告RV東照明 Reporting Issue RVE Lighting] column does not mention that vehicle.
I tried my best to explain this in my screenshot, please let me know if you need clarification.